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1 \input texinfo @c -*- Texinfo -*-
2 @setfilename binutils.info
3 @settitle @sc{gnu} Binary Utilities
4 @finalout
5 @synindex ky cp
6
7 @c man begin INCLUDE
8 @include bfdver.texi
9 @c man end
10
11 @copying
12 @c man begin COPYRIGHT
13 Copyright @copyright{} 1991-2022 Free Software Foundation, Inc.
14
15 Permission is granted to copy, distribute and/or modify this document
16 under the terms of the GNU Free Documentation License, Version 1.3
17 or any later version published by the Free Software Foundation;
18 with no Invariant Sections, with no Front-Cover Texts, and with no
19 Back-Cover Texts. A copy of the license is included in the
20 section entitled ``GNU Free Documentation License''.
21
22 @c man end
23 @end copying
24
25 @dircategory Software development
26 @direntry
27 * Binutils: (binutils). The GNU binary utilities.
28 @end direntry
29
30 @dircategory Individual utilities
31 @direntry
32 * addr2line: (binutils)addr2line. Convert addresses to file and line.
33 * ar: (binutils)ar. Create, modify, and extract from archives.
34 * c++filt: (binutils)c++filt. Filter to demangle encoded C++ symbols.
35 * cxxfilt: (binutils)c++filt. MS-DOS name for c++filt.
36 * dlltool: (binutils)dlltool. Create files needed to build and use DLLs.
37 * nm: (binutils)nm. List symbols from object files.
38 * objcopy: (binutils)objcopy. Copy and translate object files.
39 * objdump: (binutils)objdump. Display information from object files.
40 * ranlib: (binutils)ranlib. Generate index to archive contents.
41 * readelf: (binutils)readelf. Display the contents of ELF format files.
42 * size: (binutils)size. List section sizes and total size.
43 * strings: (binutils)strings. List printable strings from files.
44 * strip: (binutils)strip. Discard symbols.
45 * elfedit: (binutils)elfedit. Update ELF header and property of ELF files.
46 * windmc: (binutils)windmc. Generator for Windows message resources.
47 * windres: (binutils)windres. Manipulate Windows resources.
48 @end direntry
49
50 @titlepage
51 @title The @sc{gnu} Binary Utilities
52 @ifset VERSION_PACKAGE
53 @subtitle @value{VERSION_PACKAGE}
54 @end ifset
55 @subtitle Version @value{VERSION}
56 @sp 1
57 @subtitle @value{UPDATED}
58 @author Roland H. Pesch
59 @author Jeffrey M. Osier
60 @author Cygnus Support
61 @page
62
63 @tex
64 {\parskip=0pt \hfill Cygnus Support\par \hfill
65 Texinfo \texinfoversion\par }
66 @end tex
67
68 @vskip 0pt plus 1filll
69 @insertcopying
70 @end titlepage
71 @contents
72
73 @node Top
74 @top Introduction
75
76 @cindex version
77 This brief manual contains documentation for the @sc{gnu} binary
78 utilities
79 @ifset VERSION_PACKAGE
80 @value{VERSION_PACKAGE}
81 @end ifset
82 version @value{VERSION}:
83
84 @iftex
85 @table @code
86 @item ar
87 Create, modify, and extract from archives
88
89 @item nm
90 List symbols from object files
91
92 @item objcopy
93 Copy and translate object files
94
95 @item objdump
96 Display information from object files
97
98 @item ranlib
99 Generate index to archive contents
100
101 @item readelf
102 Display the contents of ELF format files.
103
104 @item size
105 List file section sizes and total size
106
107 @item strings
108 List printable strings from files
109
110 @item strip
111 Discard symbols
112
113 @item elfedit
114 Update the ELF header and program property of ELF files.
115
116 @item c++filt
117 Demangle encoded C++ symbols (on MS-DOS, this program is named
118 @code{cxxfilt})
119
120 @item addr2line
121 Convert addresses or symbol+offset into file names and line numbers
122
123 @item windres
124 Manipulate Windows resources
125
126 @item windmc
127 Generator for Windows message resources
128
129 @item dlltool
130 Create the files needed to build and use Dynamic Link Libraries
131 @end table
132 @end iftex
133
134 This document is distributed under the terms of the GNU Free
135 Documentation License version 1.3. A copy of the license is included
136 in the section entitled ``GNU Free Documentation License''.
137
138 @menu
139 * ar:: Create, modify, and extract from archives
140 * nm:: List symbols from object files
141 * objcopy:: Copy and translate object files
142 * objdump:: Display information from object files
143 * ranlib:: Generate index to archive contents
144 * size:: List section sizes and total size
145 * strings:: List printable strings from files
146 * strip:: Discard symbols
147 * c++filt:: Filter to demangle encoded C++ symbols
148 * cxxfilt: c++filt. MS-DOS name for c++filt
149 * addr2line:: Convert addresses or symbol+offset to file and line
150 * windmc:: Generator for Windows message resources
151 * windres:: Manipulate Windows resources
152 * dlltool:: Create files needed to build and use DLLs
153 * readelf:: Display the contents of ELF format files
154 * elfedit:: Update ELF header and property of ELF files
155 * Common Options:: Command-line options for all utilities
156 * Selecting the Target System:: How these utilities determine the target
157 * debuginfod:: Using binutils with debuginfod
158 * Reporting Bugs:: Reporting Bugs
159 * GNU Free Documentation License:: GNU Free Documentation License
160 * Binutils Index:: Binutils Index
161 @end menu
162
163 @node ar
164 @chapter ar
165
166 @kindex ar
167 @cindex archives
168 @cindex collections of files
169
170 @c man title ar create, modify, and extract from archives
171
172 @smallexample
173 ar [-]@var{p}[@var{mod}] [@option{--plugin} @var{name}] [@option{--target} @var{bfdname}] [@option{--output} @var{dirname}] [@option{--record-libdeps} @var{libdeps}] [@var{relpos}] [@var{count}] @var{archive} [@var{member}@dots{}]
174 ar -M [ <mri-script ]
175 @end smallexample
176
177 @c man begin DESCRIPTION ar
178
179 The @sc{gnu} @command{ar} program creates, modifies, and extracts from
180 archives. An @dfn{archive} is a single file holding a collection of
181 other files in a structure that makes it possible to retrieve
182 the original individual files (called @dfn{members} of the archive).
183
184 The original files' contents, mode (permissions), timestamp, owner, and
185 group are preserved in the archive, and can be restored on
186 extraction.
187
188 @cindex name length
189 @sc{gnu} @command{ar} can maintain archives whose members have names of any
190 length; however, depending on how @command{ar} is configured on your
191 system, a limit on member-name length may be imposed for compatibility
192 with archive formats maintained with other tools. If it exists, the
193 limit is often 15 characters (typical of formats related to a.out) or 16
194 characters (typical of formats related to coff).
195
196 @cindex libraries
197 @command{ar} is considered a binary utility because archives of this sort
198 are most often used as @dfn{libraries} holding commonly needed
199 subroutines. Since libraries often will depend on other libraries,
200 @command{ar} can also record the dependencies of a library when the
201 @option{--record-libdeps} option is specified.
202
203 @cindex symbol index
204 @command{ar} creates an index to the symbols defined in relocatable
205 object modules in the archive when you specify the modifier @samp{s}.
206 Once created, this index is updated in the archive whenever @command{ar}
207 makes a change to its contents (save for the @samp{q} update operation).
208 An archive with such an index speeds up linking to the library, and
209 allows routines in the library to call each other without regard to
210 their placement in the archive.
211
212 You may use @samp{nm -s} or @samp{nm --print-armap} to list this index
213 table. If an archive lacks the table, another form of @command{ar} called
214 @command{ranlib} can be used to add just the table.
215
216 @cindex thin archives
217 @sc{gnu} @command{ar} can optionally create a @emph{thin} archive,
218 which contains a symbol index and references to the original copies
219 of the member files of the archive. This is useful for building
220 libraries for use within a local build tree, where the relocatable
221 objects are expected to remain available, and copying the contents of
222 each object would only waste time and space.
223
224 An archive can either be @emph{thin} or it can be normal. It cannot
225 be both at the same time. Once an archive is created its format
226 cannot be changed without first deleting it and then creating a new
227 archive in its place.
228
229 Thin archives are also @emph{flattened}, so that adding one thin
230 archive to another thin archive does not nest it, as would happen with
231 a normal archive. Instead the elements of the first archive are added
232 individually to the second archive.
233
234 The paths to the elements of the archive are stored relative to the
235 archive itself.
236
237 @cindex compatibility, @command{ar}
238 @cindex @command{ar} compatibility
239 @sc{gnu} @command{ar} is designed to be compatible with two different
240 facilities. You can control its activity using command-line options,
241 like the different varieties of @command{ar} on Unix systems; or, if you
242 specify the single command-line option @option{-M}, you can control it
243 with a script supplied via standard input, like the MRI ``librarian''
244 program.
245
246 @c man end
247
248 @menu
249 * ar cmdline:: Controlling @command{ar} on the command line
250 * ar scripts:: Controlling @command{ar} with a script
251 @end menu
252
253 @page
254 @node ar cmdline
255 @section Controlling @command{ar} on the Command Line
256
257 @smallexample
258 @c man begin SYNOPSIS ar
259 ar [@option{-X32_64}] [@option{-}]@var{p}[@var{mod}] [@option{--plugin} @var{name}] [@option{--target} @var{bfdname}] [@option{--output} @var{dirname}] [@option{--record-libdeps} @var{libdeps}] [@option{--thin}] [@var{relpos}] [@var{count}] @var{archive} [@var{member}@dots{}]
260 @c man end
261 @end smallexample
262
263 @cindex Unix compatibility, @command{ar}
264 When you use @command{ar} in the Unix style, @command{ar} insists on at least two
265 arguments to execute: one keyletter specifying the @emph{operation}
266 (optionally accompanied by other keyletters specifying
267 @emph{modifiers}), and the archive name to act on.
268
269 Most operations can also accept further @var{member} arguments,
270 specifying particular files to operate on.
271
272 @c man begin OPTIONS ar
273
274 @sc{gnu} @command{ar} allows you to mix the operation code @var{p} and modifier
275 flags @var{mod} in any order, within the first command-line argument.
276
277 If you wish, you may begin the first command-line argument with a
278 dash.
279
280 @cindex operations on archive
281 The @var{p} keyletter specifies what operation to execute; it may be
282 any of the following, but you must specify only one of them:
283
284 @table @samp
285 @item d
286 @cindex deleting from archive
287 @emph{Delete} modules from the archive. Specify the names of modules to
288 be deleted as @var{member}@dots{}; the archive is untouched if you
289 specify no files to delete.
290
291 If you specify the @samp{v} modifier, @command{ar} lists each module
292 as it is deleted.
293
294 @item m
295 @cindex moving in archive
296 Use this operation to @emph{move} members in an archive.
297
298 The ordering of members in an archive can make a difference in how
299 programs are linked using the library, if a symbol is defined in more
300 than one member.
301
302 If no modifiers are used with @code{m}, any members you name in the
303 @var{member} arguments are moved to the @emph{end} of the archive;
304 you can use the @samp{a}, @samp{b}, or @samp{i} modifiers to move them to a
305 specified place instead.
306
307 @item p
308 @cindex printing from archive
309 @emph{Print} the specified members of the archive, to the standard
310 output file. If the @samp{v} modifier is specified, show the member
311 name before copying its contents to standard output.
312
313 If you specify no @var{member} arguments, all the files in the archive are
314 printed.
315
316 @item q
317 @cindex quick append to archive
318 @emph{Quick append}; Historically, add the files @var{member}@dots{} to the end of
319 @var{archive}, without checking for replacement.
320
321 The modifiers @samp{a}, @samp{b}, and @samp{i} do @emph{not} affect this
322 operation; new members are always placed at the end of the archive.
323
324 The modifier @samp{v} makes @command{ar} list each file as it is appended.
325
326 Since the point of this operation is speed, implementations of
327 @command{ar} have the option of not updating the archive's symbol
328 table if one exists. Too many different systems however assume that
329 symbol tables are always up-to-date, so @sc{gnu} @command{ar} will
330 rebuild the table even with a quick append.
331
332 Note - @sc{gnu} @command{ar} treats the command @samp{qs} as a
333 synonym for @samp{r} - replacing already existing files in the
334 archive and appending new ones at the end.
335
336 @item r
337 @cindex replacement in archive
338 Insert the files @var{member}@dots{} into @var{archive} (with
339 @emph{replacement}). This operation differs from @samp{q} in that any
340 previously existing members are deleted if their names match those being
341 added.
342
343 If one of the files named in @var{member}@dots{} does not exist, @command{ar}
344 displays an error message, and leaves undisturbed any existing members
345 of the archive matching that name.
346
347 By default, new members are added at the end of the file; but you may
348 use one of the modifiers @samp{a}, @samp{b}, or @samp{i} to request
349 placement relative to some existing member.
350
351 The modifier @samp{v} used with this operation elicits a line of
352 output for each file inserted, along with one of the letters @samp{a} or
353 @samp{r} to indicate whether the file was appended (no old member
354 deleted) or replaced.
355
356 @item s
357 @cindex ranlib
358 Add an index to the archive, or update it if it already exists. Note
359 this command is an exception to the rule that there can only be one
360 command letter, as it is possible to use it as either a command or a
361 modifier. In either case it does the same thing.
362
363 @item t
364 @cindex contents of archive
365 Display a @emph{table} listing the contents of @var{archive}, or those
366 of the files listed in @var{member}@dots{} that are present in the
367 archive. Normally only the member name is shown, but if the modifier
368 @samp{O} is specified, then the corresponding offset of the member is also
369 displayed. Finally, in order to see the modes (permissions), timestamp,
370 owner, group, and size the @samp{v} modifier should be included.
371
372 If you do not specify a @var{member}, all files in the archive
373 are listed.
374
375 @cindex repeated names in archive
376 @cindex name duplication in archive
377 If there is more than one file with the same name (say, @samp{fie}) in
378 an archive (say @samp{b.a}), @samp{ar t b.a fie} lists only the
379 first instance; to see them all, you must ask for a complete
380 listing---in our example, @samp{ar t b.a}.
381 @c WRS only; per Gumby, this is implementation-dependent, and in a more
382 @c recent case in fact works the other way.
383
384 @item x
385 @cindex extract from archive
386 @emph{Extract} members (named @var{member}) from the archive. You can
387 use the @samp{v} modifier with this operation, to request that
388 @command{ar} list each name as it extracts it.
389
390 If you do not specify a @var{member}, all files in the archive
391 are extracted.
392
393 Files cannot be extracted from a thin archive, and there are
394 restrictions on extracting from archives created with @option{P}: The
395 paths must not be absolute, may not contain @code{..}, and any
396 subdirectories in the paths must exist. If it is desired to avoid
397 these restrictions then used the @option{--output} option to specify
398 an output directory.
399 @end table
400
401 A number of modifiers (@var{mod}) may immediately follow the @var{p}
402 keyletter, to specify variations on an operation's behavior:
403
404 @table @samp
405 @item a
406 @cindex relative placement in archive
407 Add new files @emph{after} an existing member of the
408 archive. If you use the modifier @samp{a}, the name of an existing archive
409 member must be present as the @var{relpos} argument, before the
410 @var{archive} specification.
411
412 @item b
413 Add new files @emph{before} an existing member of the
414 archive. If you use the modifier @samp{b}, the name of an existing archive
415 member must be present as the @var{relpos} argument, before the
416 @var{archive} specification. (same as @samp{i}).
417
418 @item c
419 @cindex creating archives
420 @emph{Create} the archive. The specified @var{archive} is always
421 created if it did not exist, when you request an update. But a warning is
422 issued unless you specify in advance that you expect to create it, by
423 using this modifier.
424
425 @item D
426 @cindex deterministic archives
427 @kindex --enable-deterministic-archives
428 Operate in @emph{deterministic} mode. When adding files and the archive
429 index use zero for UIDs, GIDs, timestamps, and use consistent file modes
430 for all files. When this option is used, if @command{ar} is used with
431 identical options and identical input files, multiple runs will create
432 identical output files regardless of the input files' owners, groups,
433 file modes, or modification times.
434
435 If @file{binutils} was configured with
436 @option{--enable-deterministic-archives}, then this mode is on by default.
437 It can be disabled with the @samp{U} modifier, below.
438
439 @item f
440 Truncate names in the archive. @sc{gnu} @command{ar} will normally permit file
441 names of any length. This will cause it to create archives which are
442 not compatible with the native @command{ar} program on some systems. If
443 this is a concern, the @samp{f} modifier may be used to truncate file
444 names when putting them in the archive.
445
446 @item i
447 Insert new files @emph{before} an existing member of the
448 archive. If you use the modifier @samp{i}, the name of an existing archive
449 member must be present as the @var{relpos} argument, before the
450 @var{archive} specification. (same as @samp{b}).
451
452 @item l
453 @c This modifier was accepted but not used.
454 @c whaffor ar l modifier??? presumably compat; with
455 @c what???---doc@@cygnus.com, 25jan91
456 Specify dependencies of this library. The dependencies must immediately
457 follow this option character, must use the same syntax as the linker
458 command line, and must be specified within a single argument. I.e., if
459 multiple items are needed, they must be quoted to form a single command
460 line argument. For example @samp{L "-L/usr/local/lib -lmydep1 -lmydep2"}
461
462 @item N
463 Uses the @var{count} parameter. This is used if there are multiple
464 entries in the archive with the same name. Extract or delete instance
465 @var{count} of the given name from the archive.
466
467 @item o
468 @cindex dates in archive
469 Preserve the @emph{original} dates of members when extracting them. If
470 you do not specify this modifier, files extracted from the archive
471 are stamped with the time of extraction.
472
473 @item O
474 @cindex offsets of files
475 Display member offsets inside the archive. Use together with the @samp{t}
476 option.
477
478 @item P
479 Use the full path name when matching or storing names in the archive.
480 Archives created with full path names are not POSIX compliant, and
481 thus may not work with tools other than up to date @sc{gnu} tools.
482 Modifying such archives with @sc{gnu} @command{ar} without using
483 @option{P} will remove the full path names unless the archive is a
484 thin archive. Note that @option{P} may be useful when adding files to
485 a thin archive since @option{r} without @option{P} ignores the path
486 when choosing which element to replace. Thus
487 @smallexample
488 ar rcST archive.a subdir/file1 subdir/file2 file1
489 @end smallexample
490 will result in the first @code{subdir/file1} being replaced with
491 @code{file1} from the current directory. Adding @option{P} will
492 prevent this replacement.
493
494 @item s
495 @cindex writing archive index
496 Write an object-file index into the archive, or update an existing one,
497 even if no other change is made to the archive. You may use this modifier
498 flag either with any operation, or alone. Running @samp{ar s} on an
499 archive is equivalent to running @samp{ranlib} on it.
500
501 @item S
502 @cindex not writing archive index
503 Do not generate an archive symbol table. This can speed up building a
504 large library in several steps. The resulting archive can not be used
505 with the linker. In order to build a symbol table, you must omit the
506 @samp{S} modifier on the last execution of @samp{ar}, or you must run
507 @samp{ranlib} on the archive.
508
509 @item T
510 Deprecated alias for @option{--thin}. @option{T} is not recommended because in
511 many ar implementations @option{T} has a different meaning, as specified by
512 X/Open System Interface.
513
514 @item u
515 @cindex updating an archive
516 Normally, @samp{ar r}@dots{} inserts all files
517 listed into the archive. If you would like to insert @emph{only} those
518 of the files you list that are newer than existing members of the same
519 names, use this modifier. The @samp{u} modifier is allowed only for the
520 operation @samp{r} (replace). In particular, the combination @samp{qu} is
521 not allowed, since checking the timestamps would lose any speed
522 advantage from the operation @samp{q}.
523
524 @item U
525 @cindex deterministic archives
526 @kindex --enable-deterministic-archives
527 Do @emph{not} operate in @emph{deterministic} mode. This is the inverse
528 of the @samp{D} modifier, above: added files and the archive index will
529 get their actual UID, GID, timestamp, and file mode values.
530
531 This is the default unless @file{binutils} was configured with
532 @option{--enable-deterministic-archives}.
533
534 @item v
535 This modifier requests the @emph{verbose} version of an operation. Many
536 operations display additional information, such as filenames processed,
537 when the modifier @samp{v} is appended.
538
539 @item V
540 This modifier shows the version number of @command{ar}.
541 @end table
542
543 The @command{ar} program also supports some command-line options which
544 are neither modifiers nor actions, but which do change its behaviour
545 in specific ways:
546
547 @table @samp
548 @item --help
549 Displays the list of command-line options supported by @command{ar}
550 and then exits.
551
552 @item --version
553 Displays the version information of @command{ar} and then exits.
554
555 @item -X32_64
556 @command{ar} ignores an initial option spelled @samp{-X32_64}, for
557 compatibility with AIX. The behaviour produced by this option is the
558 default for @sc{gnu} @command{ar}. @command{ar} does not support any
559 of the other @samp{-X} options; in particular, it does not support
560 @option{-X32} which is the default for AIX @command{ar}.
561
562 @item --plugin @var{name}
563 @cindex plugins
564 The optional command-line switch @option{--plugin @var{name}} causes
565 @command{ar} to load the plugin called @var{name} which adds support
566 for more file formats, including object files with link-time
567 optimization information.
568
569 This option is only available if the toolchain has been built with
570 plugin support enabled.
571
572 If @option{--plugin} is not provided, but plugin support has been
573 enabled then @command{ar} iterates over the files in
574 @file{$@{libdir@}/bfd-plugins} in alphabetic order and the first
575 plugin that claims the object in question is used.
576
577 Please note that this plugin search directory is @emph{not} the one
578 used by @command{ld}'s @option{-plugin} option. In order to make
579 @command{ar} use the linker plugin it must be copied into the
580 @file{$@{libdir@}/bfd-plugins} directory. For GCC based compilations
581 the linker plugin is called @file{liblto_plugin.so.0.0.0}. For Clang
582 based compilations it is called @file{LLVMgold.so}. The GCC plugin
583 is always backwards compatible with earlier versions, so it is
584 sufficient to just copy the newest one.
585
586 @item --target @var{target}
587 The optional command-line switch @option{--target @var{bfdname}}
588 specifies that the archive members are in an object code format
589 different from your system's default format. See
590 @xref{Target Selection}, for more information.
591
592 @item --output @var{dirname}
593 The @option{--output} option can be used to specify a path to a
594 directory into which archive members should be extracted. If this
595 option is not specified then the current directory will be used.
596
597 Note - although the presence of this option does imply a @option{x}
598 extraction operation that option must still be included on the command
599 line.
600
601 @item --record-libdeps @var{libdeps}
602 The @option{--record-libdeps} option is identical to the @option{l} modifier,
603 just handled in long form.
604
605 @item --thin
606 @cindex creating thin archive
607 Make the specified @var{archive} a @emph{thin} archive. If it already
608 exists and is a regular archive, the existing members must be present
609 in the same directory as @var{archive}.
610
611 @end table
612 @c man end
613
614 @ignore
615 @c man begin SEEALSO ar
616 nm(1), ranlib(1), and the Info entries for @file{binutils}.
617 @c man end
618 @end ignore
619
620 @node ar scripts
621 @section Controlling @command{ar} with a Script
622
623 @smallexample
624 ar -M [ <@var{script} ]
625 @end smallexample
626
627 @cindex MRI compatibility, @command{ar}
628 @cindex scripts, @command{ar}
629 If you use the single command-line option @samp{-M} with @command{ar}, you
630 can control its operation with a rudimentary command language. This
631 form of @command{ar} operates interactively if standard input is coming
632 directly from a terminal. During interactive use, @command{ar} prompts for
633 input (the prompt is @samp{AR >}), and continues executing even after
634 errors. If you redirect standard input to a script file, no prompts are
635 issued, and @command{ar} abandons execution (with a nonzero exit code)
636 on any error.
637
638 The @command{ar} command language is @emph{not} designed to be equivalent
639 to the command-line options; in fact, it provides somewhat less control
640 over archives. The only purpose of the command language is to ease the
641 transition to @sc{gnu} @command{ar} for developers who already have scripts
642 written for the MRI ``librarian'' program.
643
644 The syntax for the @command{ar} command language is straightforward:
645 @itemize @bullet
646 @item
647 commands are recognized in upper or lower case; for example, @code{LIST}
648 is the same as @code{list}. In the following descriptions, commands are
649 shown in upper case for clarity.
650
651 @item
652 a single command may appear on each line; it is the first word on the
653 line.
654
655 @item
656 empty lines are allowed, and have no effect.
657
658 @item
659 comments are allowed; text after either of the characters @samp{*}
660 or @samp{;} is ignored.
661
662 @item
663 Whenever you use a list of names as part of the argument to an @command{ar}
664 command, you can separate the individual names with either commas or
665 blanks. Commas are shown in the explanations below, for clarity.
666
667 @item
668 @samp{+} is used as a line continuation character; if @samp{+} appears
669 at the end of a line, the text on the following line is considered part
670 of the current command.
671 @end itemize
672
673 Here are the commands you can use in @command{ar} scripts, or when using
674 @command{ar} interactively. Three of them have special significance:
675
676 @code{OPEN} or @code{CREATE} specify a @dfn{current archive}, which is
677 a temporary file required for most of the other commands.
678
679 @code{SAVE} commits the changes so far specified by the script. Prior
680 to @code{SAVE}, commands affect only the temporary copy of the current
681 archive.
682
683 @table @code
684 @item ADDLIB @var{archive}
685 @itemx ADDLIB @var{archive} (@var{module}, @var{module}, @dots{} @var{module})
686 Add all the contents of @var{archive} (or, if specified, each named
687 @var{module} from @var{archive}) to the current archive.
688
689 Requires prior use of @code{OPEN} or @code{CREATE}.
690
691 @item ADDMOD @var{member}, @var{member}, @dots{} @var{member}
692 @c FIXME! w/Replacement?? If so, like "ar r @var{archive} @var{names}"
693 @c else like "ar q..."
694 Add each named @var{member} as a module in the current archive.
695
696 Requires prior use of @code{OPEN} or @code{CREATE}.
697
698 @item CLEAR
699 Discard the contents of the current archive, canceling the effect of
700 any operations since the last @code{SAVE}. May be executed (with no
701 effect) even if no current archive is specified.
702
703 @item CREATE @var{archive}
704 Creates an archive, and makes it the current archive (required for many
705 other commands). The new archive is created with a temporary name; it
706 is not actually saved as @var{archive} until you use @code{SAVE}.
707 You can overwrite existing archives; similarly, the contents of any
708 existing file named @var{archive} will not be destroyed until @code{SAVE}.
709
710 @item DELETE @var{module}, @var{module}, @dots{} @var{module}
711 Delete each listed @var{module} from the current archive; equivalent to
712 @samp{ar -d @var{archive} @var{module} @dots{} @var{module}}.
713
714 Requires prior use of @code{OPEN} or @code{CREATE}.
715
716 @item DIRECTORY @var{archive} (@var{module}, @dots{} @var{module})
717 @itemx DIRECTORY @var{archive} (@var{module}, @dots{} @var{module}) @var{outputfile}
718 List each named @var{module} present in @var{archive}. The separate
719 command @code{VERBOSE} specifies the form of the output: when verbose
720 output is off, output is like that of @samp{ar -t @var{archive}
721 @var{module}@dots{}}. When verbose output is on, the listing is like
722 @samp{ar -tv @var{archive} @var{module}@dots{}}.
723
724 Output normally goes to the standard output stream; however, if you
725 specify @var{outputfile} as a final argument, @command{ar} directs the
726 output to that file.
727
728 @item END
729 Exit from @command{ar}, with a @code{0} exit code to indicate successful
730 completion. This command does not save the output file; if you have
731 changed the current archive since the last @code{SAVE} command, those
732 changes are lost.
733
734 @item EXTRACT @var{module}, @var{module}, @dots{} @var{module}
735 Extract each named @var{module} from the current archive, writing them
736 into the current directory as separate files. Equivalent to @samp{ar -x
737 @var{archive} @var{module}@dots{}}.
738
739 Requires prior use of @code{OPEN} or @code{CREATE}.
740
741 @ignore
742 @c FIXME Tokens but no commands???
743 @item FULLDIR
744
745 @item HELP
746 @end ignore
747
748 @item LIST
749 Display full contents of the current archive, in ``verbose'' style
750 regardless of the state of @code{VERBOSE}. The effect is like @samp{ar
751 tv @var{archive}}. (This single command is a @sc{gnu} @command{ar}
752 enhancement, rather than present for MRI compatibility.)
753
754 Requires prior use of @code{OPEN} or @code{CREATE}.
755
756 @item OPEN @var{archive}
757 Opens an existing archive for use as the current archive (required for
758 many other commands). Any changes as the result of subsequent commands
759 will not actually affect @var{archive} until you next use @code{SAVE}.
760
761 @item REPLACE @var{module}, @var{module}, @dots{} @var{module}
762 In the current archive, replace each existing @var{module} (named in
763 the @code{REPLACE} arguments) from files in the current working directory.
764 To execute this command without errors, both the file, and the module in
765 the current archive, must exist.
766
767 Requires prior use of @code{OPEN} or @code{CREATE}.
768
769 @item VERBOSE
770 Toggle an internal flag governing the output from @code{DIRECTORY}.
771 When the flag is on, @code{DIRECTORY} output matches output from
772 @samp{ar -tv }@dots{}.
773
774 @item SAVE
775 Commit your changes to the current archive, and actually save it as a
776 file with the name specified in the last @code{CREATE} or @code{OPEN}
777 command.
778
779 Requires prior use of @code{OPEN} or @code{CREATE}.
780
781 @end table
782
783 @iftex
784 @node ld
785 @chapter ld
786 @cindex linker
787 @kindex ld
788 The @sc{gnu} linker @command{ld} is now described in a separate manual.
789 @xref{Top,, Overview,, Using LD: the @sc{gnu} linker}.
790 @end iftex
791
792 @node nm
793 @chapter nm
794 @cindex symbols
795 @kindex nm
796
797 @c man title nm list symbols from object files
798
799 @smallexample
800 @c man begin SYNOPSIS nm
801 nm [@option{-A}|@option{-o}|@option{--print-file-name}]
802 [@option{-a}|@option{--debug-syms}]
803 [@option{-B}|@option{--format=bsd}]
804 [@option{-C}|@option{--demangle}[=@var{style}]]
805 [@option{-D}|@option{--dynamic}]
806 [@option{-f}@var{format}|@option{--format=}@var{format}]
807 [@option{-g}|@option{--extern-only}]
808 [@option{-h}|@option{--help}]
809 [@option{--ifunc-chars=@var{CHARS}}]
810 [@option{-j}|@option{--format=just-symbols}]
811 [@option{-l}|@option{--line-numbers}] [@option{--inlines}]
812 [@option{-n}|@option{-v}|@option{--numeric-sort}]
813 [@option{-P}|@option{--portability}]
814 [@option{-p}|@option{--no-sort}]
815 [@option{-r}|@option{--reverse-sort}]
816 [@option{-S}|@option{--print-size}]
817 [@option{-s}|@option{--print-armap}]
818 [@option{-t} @var{radix}|@option{--radix=}@var{radix}]
819 [@option{-u}|@option{--undefined-only}]
820 [@option{-U}|@option{--defined-only}]
821 [@option{-V}|@option{--version}]
822 [@option{-W}|@option{--no-weak}]
823 [@option{-X 32_64}]
824 [@option{--no-demangle}]
825 [@option{--no-recurse-limit}|@option{--recurse-limit}]]
826 [@option{--plugin} @var{name}]
827 [@option{--size-sort}]
828 [@option{--special-syms}]
829 [@option{--synthetic}]
830 [@option{--target=}@var{bfdname}]
831 [@option{--unicode=}@var{method}]
832 [@option{--with-symbol-versions}]
833 [@option{--without-symbol-versions}]
834 [@var{objfile}@dots{}]
835 @c man end
836 @end smallexample
837
838 @c man begin DESCRIPTION nm
839 @sc{gnu} @command{nm} lists the symbols from object files @var{objfile}@dots{}.
840 If no object files are listed as arguments, @command{nm} assumes the file
841 @file{a.out}.
842
843 For each symbol, @command{nm} shows:
844
845 @itemize @bullet
846 @item
847 The symbol value, in the radix selected by options (see below), or
848 hexadecimal by default.
849
850 @item
851 The symbol type. At least the following types are used; others are, as
852 well, depending on the object file format. If lowercase, the symbol is
853 usually local; if uppercase, the symbol is global (external). There
854 are however a few lowercase symbols that are shown for special global
855 symbols (@code{u}, @code{v} and @code{w}).
856
857 @c Some more detail on exactly what these symbol types are used for
858 @c would be nice.
859 @table @code
860 @item A
861 The symbol's value is absolute, and will not be changed by further
862 linking.
863
864 @item B
865 @itemx b
866 The symbol is in the BSS data section. This section typically
867 contains zero-initialized or uninitialized data, although the exact
868 behavior is system dependent.
869
870 @item C
871 @itemx c
872 The symbol is common. Common symbols are uninitialized data. When
873 linking, multiple common symbols may appear with the same name. If the
874 symbol is defined anywhere, the common symbols are treated as undefined
875 references.
876 @ifclear man
877 For more details on common symbols, see the discussion of
878 --warn-common in @ref{Options,,Linker options,ld.info,The GNU linker}.
879 @end ifclear
880 The lower case @var{c} character is used when the symbol is in a
881 special section for small commons.
882
883 @item D
884 @itemx d
885 The symbol is in the initialized data section.
886
887 @item G
888 @itemx g
889 The symbol is in an initialized data section for small objects. Some
890 object file formats permit more efficient access to small data objects,
891 such as a global int variable as opposed to a large global array.
892
893 @item i
894 For PE format files this indicates that the symbol is in a section
895 specific to the implementation of DLLs.
896
897 For ELF format files this indicates that the symbol is an indirect
898 function. This is a GNU extension to the standard set of ELF symbol
899 types. It indicates a symbol which if referenced by a relocation does
900 not evaluate to its address, but instead must be invoked at runtime.
901 The runtime execution will then return the value to be used in the
902 relocation.
903
904 Note - the actual symbols display for GNU indirect symbols is
905 controlled by the @option{--ifunc-chars} command line option. If this
906 option has been provided then the first character in the string will
907 be used for global indirect function symbols. If the string contains
908 a second character then that will be used for local indirect function
909 symbols.
910
911 @item I
912 The symbol is an indirect reference to another symbol.
913
914 @item N
915 The symbol is a debugging symbol.
916
917 @item n
918 The symbol is in the read-only data section.
919
920 @item p
921 The symbol is in a stack unwind section.
922
923 @item R
924 @itemx r
925 The symbol is in a read only data section.
926
927 @item S
928 @itemx s
929 The symbol is in an uninitialized or zero-initialized data section
930 for small objects.
931
932 @item T
933 @itemx t
934 The symbol is in the text (code) section.
935
936 @item U
937 The symbol is undefined.
938
939 @item u
940 The symbol is a unique global symbol. This is a GNU extension to the
941 standard set of ELF symbol bindings. For such a symbol the dynamic linker
942 will make sure that in the entire process there is just one symbol with
943 this name and type in use.
944
945 @item V
946 @itemx v
947 The symbol is a weak object. When a weak defined symbol is linked with
948 a normal defined symbol, the normal defined symbol is used with no error.
949 When a weak undefined symbol is linked and the symbol is not defined,
950 the value of the weak symbol becomes zero with no error. On some
951 systems, uppercase indicates that a default value has been specified.
952
953 @item W
954 @itemx w
955 The symbol is a weak symbol that has not been specifically tagged as a
956 weak object symbol. When a weak defined symbol is linked with a normal
957 defined symbol, the normal defined symbol is used with no error.
958 When a weak undefined symbol is linked and the symbol is not defined,
959 the value of the symbol is determined in a system-specific manner without
960 error. On some systems, uppercase indicates that a default value has been
961 specified.
962
963 @item -
964 The symbol is a stabs symbol in an a.out object file. In this case, the
965 next values printed are the stabs other field, the stabs desc field, and
966 the stab type. Stabs symbols are used to hold debugging information.
967
968 @item ?
969 The symbol type is unknown, or object file format specific.
970 @end table
971
972 @item
973 The symbol name. If a symbol has version information associated with it,
974 then the version information is displayed as well. If the versioned
975 symbol is undefined or hidden from linker, the version string is displayed
976 as a suffix to the symbol name, preceded by an @@ character. For example
977 @samp{foo@@VER_1}. If the version is the default version to be used when
978 resolving unversioned references to the symbol, then it is displayed as a
979 suffix preceded by two @@ characters. For example @samp{foo@@@@VER_2}.
980 @end itemize
981
982 @c man end
983
984 @c man begin OPTIONS nm
985 The long and short forms of options, shown here as alternatives, are
986 equivalent.
987
988 @table @env
989 @item -A
990 @itemx -o
991 @itemx --print-file-name
992 @cindex input file name
993 @cindex file name
994 @cindex source file name
995 Precede each symbol by the name of the input file (or archive member)
996 in which it was found, rather than identifying the input file once only,
997 before all of its symbols.
998
999 @item -a
1000 @itemx --debug-syms
1001 @cindex debugging symbols
1002 Display all symbols, even debugger-only symbols; normally these are not
1003 listed.
1004
1005 @item -B
1006 @cindex @command{nm} format
1007 @cindex @command{nm} compatibility
1008 The same as @option{--format=bsd} (for compatibility with the MIPS @command{nm}).
1009
1010 @item -C
1011 @itemx --demangle[=@var{style}]
1012 @cindex demangling in nm
1013 Decode (@dfn{demangle}) low-level symbol names into user-level names.
1014 Besides removing any initial underscore prepended by the system, this
1015 makes C++ function names readable. Different compilers have different
1016 mangling styles. The optional demangling style argument can be used to
1017 choose an appropriate demangling style for your compiler. @xref{c++filt},
1018 for more information on demangling.
1019
1020 @item --no-demangle
1021 Do not demangle low-level symbol names. This is the default.
1022
1023 @item --recurse-limit
1024 @itemx --no-recurse-limit
1025 @itemx --recursion-limit
1026 @itemx --no-recursion-limit
1027 Enables or disables a limit on the amount of recursion performed
1028 whilst demangling strings. Since the name mangling formats allow for
1029 an infinite level of recursion it is possible to create strings whose
1030 decoding will exhaust the amount of stack space available on the host
1031 machine, triggering a memory fault. The limit tries to prevent this
1032 from happening by restricting recursion to 2048 levels of nesting.
1033
1034 The default is for this limit to be enabled, but disabling it may be
1035 necessary in order to demangle truly complicated names. Note however
1036 that if the recursion limit is disabled then stack exhaustion is
1037 possible and any bug reports about such an event will be rejected.
1038
1039 @item -D
1040 @itemx --dynamic
1041 @cindex dynamic symbols
1042 Display the dynamic symbols rather than the normal symbols. This is
1043 only meaningful for dynamic objects, such as certain types of shared
1044 libraries.
1045
1046 @item -f @var{format}
1047 @itemx --format=@var{format}
1048 @cindex @command{nm} format
1049 @cindex @command{nm} compatibility
1050 Use the output format @var{format}, which can be @code{bsd},
1051 @code{sysv}, @code{posix} or @code{just-symbols}. The default is @code{bsd}.
1052 Only the first character of @var{format} is significant; it can be
1053 either upper or lower case.
1054
1055 @item -g
1056 @itemx --extern-only
1057 @cindex external symbols
1058 Display only external symbols.
1059
1060 @item -h
1061 @itemx --help
1062 Show a summary of the options to @command{nm} and exit.
1063
1064 @item --ifunc-chars=@var{CHARS}
1065 When display GNU indirect function symbols @command{nm} will default
1066 to using the @code{i} character for both local indirect functions and
1067 global indirect functions. The @option{--ifunc-chars} option allows
1068 the user to specify a string containing one or two characters. The
1069 first character will be used for global indirect function symbols and
1070 the second character, if present, will be used for local indirect
1071 function symbols.
1072
1073 @item j
1074 The same as @option{--format=just-symbols}.
1075
1076 @item -l
1077 @itemx --line-numbers
1078 @cindex symbol line numbers
1079 For each symbol, use debugging information to try to find a filename and
1080 line number. For a defined symbol, look for the line number of the
1081 address of the symbol. For an undefined symbol, look for the line
1082 number of a relocation entry which refers to the symbol. If line number
1083 information can be found, print it after the other symbol information.
1084
1085 @item --inlines
1086 @cindex objdump inlines
1087 When option @option{-l} is active, if the address belongs to a
1088 function that was inlined, then this option causes the source
1089 information for all enclosing scopes back to the first non-inlined
1090 function to be printed as well. For example, if @code{main} inlines
1091 @code{callee1} which inlines @code{callee2}, and address is from
1092 @code{callee2}, the source information for @code{callee1} and @code{main}
1093 will also be printed.
1094
1095 @item -n
1096 @itemx -v
1097 @itemx --numeric-sort
1098 Sort symbols numerically by their addresses, rather than alphabetically
1099 by their names.
1100
1101 @item -p
1102 @itemx --no-sort
1103 @cindex sorting symbols
1104 Do not bother to sort the symbols in any order; print them in the order
1105 encountered.
1106
1107 @item -P
1108 @itemx --portability
1109 Use the POSIX.2 standard output format instead of the default format.
1110 Equivalent to @samp{-f posix}.
1111
1112 @item -r
1113 @itemx --reverse-sort
1114 Reverse the order of the sort (whether numeric or alphabetic); let the
1115 last come first.
1116
1117 @item -S
1118 @itemx --print-size
1119 Print both value and size of defined symbols for the @code{bsd} output style.
1120 This option has no effect for object formats that do not record symbol
1121 sizes, unless @samp{--size-sort} is also used in which case a
1122 calculated size is displayed.
1123
1124 @item -s
1125 @itemx --print-armap
1126 @cindex symbol index, listing
1127 When listing symbols from archive members, include the index: a mapping
1128 (stored in the archive by @command{ar} or @command{ranlib}) of which modules
1129 contain definitions for which names.
1130
1131 @item -t @var{radix}
1132 @itemx --radix=@var{radix}
1133 Use @var{radix} as the radix for printing the symbol values. It must be
1134 @samp{d} for decimal, @samp{o} for octal, or @samp{x} for hexadecimal.
1135
1136 @item -u
1137 @itemx --undefined-only
1138 @cindex external symbols
1139 @cindex undefined symbols
1140 Display only undefined symbols (those external to each object file).
1141 By default both defined and undefined symbols are displayed.
1142
1143 @item -U
1144 @itemx --defined-only
1145 @cindex external symbols
1146 @cindex undefined symbols
1147 Display only defined symbols for each object file.
1148 By default both defined and undefined symbols are displayed.
1149
1150 @item -V
1151 @itemx --version
1152 Show the version number of @command{nm} and exit.
1153
1154 @item -X
1155 This option is ignored for compatibility with the AIX version of
1156 @command{nm}. It takes one parameter which must be the string
1157 @option{32_64}. The default mode of AIX @command{nm} corresponds
1158 to @option{-X 32}, which is not supported by @sc{gnu} @command{nm}.
1159
1160 @item --plugin @var{name}
1161 @cindex plugins
1162 Load the plugin called @var{name} to add support for extra target
1163 types. This option is only available if the toolchain has been built
1164 with plugin support enabled.
1165
1166 If @option{--plugin} is not provided, but plugin support has been
1167 enabled then @command{nm} iterates over the files in
1168 @file{$@{libdir@}/bfd-plugins} in alphabetic order and the first
1169 plugin that claims the object in question is used.
1170
1171 Please note that this plugin search directory is @emph{not} the one
1172 used by @command{ld}'s @option{-plugin} option. In order to make
1173 @command{nm} use the linker plugin it must be copied into the
1174 @file{$@{libdir@}/bfd-plugins} directory. For GCC based compilations
1175 the linker plugin is called @file{liblto_plugin.so.0.0.0}. For Clang
1176 based compilations it is called @file{LLVMgold.so}. The GCC plugin
1177 is always backwards compatible with earlier versions, so it is
1178 sufficient to just copy the newest one.
1179
1180 @item --size-sort
1181 Sort symbols by size. For ELF objects symbol sizes are read from the
1182 ELF, for other object types the symbol sizes are computed as the
1183 difference between the value of the symbol and the value of the symbol
1184 with the next higher value. If the @code{bsd} output format is used
1185 the size of the symbol is printed, rather than the value, and
1186 @samp{-S} must be used in order both size and value to be printed.
1187
1188 Note - this option does not work if @option{--undefined-only} has been
1189 enabled as undefined symbols have no size.
1190
1191 @item --special-syms
1192 Display symbols which have a target-specific special meaning. These
1193 symbols are usually used by the target for some special processing and
1194 are not normally helpful when included in the normal symbol lists.
1195 For example for ARM targets this option would skip the mapping symbols
1196 used to mark transitions between ARM code, THUMB code and data.
1197
1198 @item --synthetic
1199 Include synthetic symbols in the output. These are special symbols
1200 created by the linker for various purposes. They are not shown by
1201 default since they are not part of the binary's original source code.
1202
1203 @item --unicode=@var{[default|invalid|locale|escape|hex|highlight]}
1204 Controls the display of UTF-8 encoded multibyte characters in strings.
1205 The default (@option{--unicode=default}) is to give them no special
1206 treatment. The @option{--unicode=locale} option displays the sequence
1207 in the current locale, which may or may not support them. The options
1208 @option{--unicode=hex} and @option{--unicode=invalid} display them as
1209 hex byte sequences enclosed by either angle brackets or curly braces.
1210
1211 The @option{--unicode=escape} option displays them as escape sequences
1212 (@var{\uxxxx}) and the @option{--unicode=highlight} option displays
1213 them as escape sequences highlighted in red (if supported by the
1214 output device). The colouring is intended to draw attention to the
1215 presence of unicode sequences where they might not be expected.
1216
1217 @item -W
1218 @itemx --no-weak
1219 Do not display weak symbols.
1220
1221 @item --with-symbol-versions
1222 @item --without-symbol-versions
1223 Enables or disables the display of symbol version information. The
1224 version string is displayed as a suffix to the symbol name, preceded
1225 by an @@ character. For example @samp{foo@@VER_1}. If the version is
1226 the default version to be used when resolving unversioned references
1227 to the symbol then it is displayed as a suffix preceded by two @@
1228 characters. For example @samp{foo@@@@VER_2}. By default, symbol
1229 version information is displayed.
1230
1231 @item --target=@var{bfdname}
1232 @cindex object code format
1233 Specify an object code format other than your system's default format.
1234 @xref{Target Selection}, for more information.
1235
1236 @end table
1237
1238 @c man end
1239
1240 @ignore
1241 @c man begin SEEALSO nm
1242 ar(1), objdump(1), ranlib(1), and the Info entries for @file{binutils}.
1243 @c man end
1244 @end ignore
1245
1246 @node objcopy
1247 @chapter objcopy
1248
1249 @c man title objcopy copy and translate object files
1250
1251 @smallexample
1252 @c man begin SYNOPSIS objcopy
1253 objcopy [@option{-F} @var{bfdname}|@option{--target=}@var{bfdname}]
1254 [@option{-I} @var{bfdname}|@option{--input-target=}@var{bfdname}]
1255 [@option{-O} @var{bfdname}|@option{--output-target=}@var{bfdname}]
1256 [@option{-B} @var{bfdarch}|@option{--binary-architecture=}@var{bfdarch}]
1257 [@option{-S}|@option{--strip-all}]
1258 [@option{-g}|@option{--strip-debug}]
1259 [@option{--strip-unneeded}]
1260 [@option{-K} @var{symbolname}|@option{--keep-symbol=}@var{symbolname}]
1261 [@option{--keep-file-symbols}]
1262 [@option{--keep-section-symbols}]
1263 [@option{-N} @var{symbolname}|@option{--strip-symbol=}@var{symbolname}]
1264 [@option{--strip-unneeded-symbol=}@var{symbolname}]
1265 [@option{-G} @var{symbolname}|@option{--keep-global-symbol=}@var{symbolname}]
1266 [@option{--localize-hidden}]
1267 [@option{-L} @var{symbolname}|@option{--localize-symbol=}@var{symbolname}]
1268 [@option{--globalize-symbol=}@var{symbolname}]
1269 [@option{--globalize-symbols=}@var{filename}]
1270 [@option{-W} @var{symbolname}|@option{--weaken-symbol=}@var{symbolname}]
1271 [@option{-w}|@option{--wildcard}]
1272 [@option{-x}|@option{--discard-all}]
1273 [@option{-X}|@option{--discard-locals}]
1274 [@option{-b} @var{byte}|@option{--byte=}@var{byte}]
1275 [@option{-i} [@var{breadth}]|@option{--interleave}[=@var{breadth}]]
1276 [@option{--interleave-width=}@var{width}]
1277 [@option{-j} @var{sectionpattern}|@option{--only-section=}@var{sectionpattern}]
1278 [@option{-R} @var{sectionpattern}|@option{--remove-section=}@var{sectionpattern}]
1279 [@option{--keep-section=}@var{sectionpattern}]
1280 [@option{--remove-relocations=}@var{sectionpattern}]
1281 [@option{-p}|@option{--preserve-dates}]
1282 [@option{-D}|@option{--enable-deterministic-archives}]
1283 [@option{-U}|@option{--disable-deterministic-archives}]
1284 [@option{--debugging}]
1285 [@option{--gap-fill=}@var{val}]
1286 [@option{--pad-to=}@var{address}]
1287 [@option{--set-start=}@var{val}]
1288 [@option{--adjust-start=}@var{incr}]
1289 [@option{--change-addresses=}@var{incr}]
1290 [@option{--change-section-address} @var{sectionpattern}@{=,+,-@}@var{val}]
1291 [@option{--change-section-lma} @var{sectionpattern}@{=,+,-@}@var{val}]
1292 [@option{--change-section-vma} @var{sectionpattern}@{=,+,-@}@var{val}]
1293 [@option{--change-warnings}] [@option{--no-change-warnings}]
1294 [@option{--set-section-flags} @var{sectionpattern}=@var{flags}]
1295 [@option{--set-section-alignment} @var{sectionpattern}=@var{align}]
1296 [@option{--add-section} @var{sectionname}=@var{filename}]
1297 [@option{--dump-section} @var{sectionname}=@var{filename}]
1298 [@option{--update-section} @var{sectionname}=@var{filename}]
1299 [@option{--rename-section} @var{oldname}=@var{newname}[,@var{flags}]]
1300 [@option{--long-section-names} @{enable,disable,keep@}]
1301 [@option{--change-leading-char}] [@option{--remove-leading-char}]
1302 [@option{--reverse-bytes=}@var{num}]
1303 [@option{--srec-len=}@var{ival}] [@option{--srec-forceS3}]
1304 [@option{--redefine-sym} @var{old}=@var{new}]
1305 [@option{--redefine-syms=}@var{filename}]
1306 [@option{--weaken}]
1307 [@option{--keep-symbols=}@var{filename}]
1308 [@option{--strip-symbols=}@var{filename}]
1309 [@option{--strip-unneeded-symbols=}@var{filename}]
1310 [@option{--keep-global-symbols=}@var{filename}]
1311 [@option{--localize-symbols=}@var{filename}]
1312 [@option{--weaken-symbols=}@var{filename}]
1313 [@option{--add-symbol} @var{name}=[@var{section}:]@var{value}[,@var{flags}]]
1314 [@option{--alt-machine-code=}@var{index}]
1315 [@option{--prefix-symbols=}@var{string}]
1316 [@option{--prefix-sections=}@var{string}]
1317 [@option{--prefix-alloc-sections=}@var{string}]
1318 [@option{--add-gnu-debuglink=}@var{path-to-file}]
1319 [@option{--only-keep-debug}]
1320 [@option{--strip-dwo}]
1321 [@option{--extract-dwo}]
1322 [@option{--extract-symbol}]
1323 [@option{--writable-text}]
1324 [@option{--readonly-text}]
1325 [@option{--pure}]
1326 [@option{--impure}]
1327 [@option{--file-alignment=}@var{num}]
1328 [@option{--heap=}@var{size}]
1329 [@option{--image-base=}@var{address}]
1330 [@option{--section-alignment=}@var{num}]
1331 [@option{--stack=}@var{size}]
1332 [@option{--subsystem=}@var{which}:@var{major}.@var{minor}]
1333 [@option{--compress-debug-sections}]
1334 [@option{--decompress-debug-sections}]
1335 [@option{--elf-stt-common=@var{val}}]
1336 [@option{--merge-notes}]
1337 [@option{--no-merge-notes}]
1338 [@option{--verilog-data-width=@var{val}}]
1339 [@option{-v}|@option{--verbose}]
1340 [@option{-V}|@option{--version}]
1341 [@option{--help}] [@option{--info}]
1342 @var{infile} [@var{outfile}]
1343 @c man end
1344 @end smallexample
1345
1346 @c man begin DESCRIPTION objcopy
1347 The @sc{gnu} @command{objcopy} utility copies the contents of an object
1348 file to another. @command{objcopy} uses the @sc{gnu} @sc{bfd} Library to
1349 read and write the object files. It can write the destination object
1350 file in a format different from that of the source object file. The
1351 exact behavior of @command{objcopy} is controlled by command-line options.
1352 Note that @command{objcopy} should be able to copy a fully linked file
1353 between any two formats. However, copying a relocatable object file
1354 between any two formats may not work as expected.
1355
1356 @command{objcopy} creates temporary files to do its translations and
1357 deletes them afterward. @command{objcopy} uses @sc{bfd} to do all its
1358 translation work; it has access to all the formats described in @sc{bfd}
1359 and thus is able to recognize most formats without being told
1360 explicitly. @xref{BFD,,BFD,ld.info,Using LD}.
1361
1362 @command{objcopy} can be used to generate S-records by using an output
1363 target of @samp{srec} (e.g., use @samp{-O srec}).
1364
1365 @command{objcopy} can be used to generate a raw binary file by using an
1366 output target of @samp{binary} (e.g., use @option{-O binary}). When
1367 @command{objcopy} generates a raw binary file, it will essentially produce
1368 a memory dump of the contents of the input object file. All symbols and
1369 relocation information will be discarded. The memory dump will start at
1370 the load address of the lowest section copied into the output file.
1371
1372 When generating an S-record or a raw binary file, it may be helpful to
1373 use @option{-S} to remove sections containing debugging information. In
1374 some cases @option{-R} will be useful to remove sections which contain
1375 information that is not needed by the binary file.
1376
1377 Note---@command{objcopy} is not able to change the endianness of its input
1378 files. If the input format has an endianness (some formats do not),
1379 @command{objcopy} can only copy the inputs into file formats that have the
1380 same endianness or which have no endianness (e.g., @samp{srec}).
1381 (However, see the @option{--reverse-bytes} option.)
1382
1383 @c man end
1384
1385 @c man begin OPTIONS objcopy
1386
1387 @table @env
1388 @item @var{infile}
1389 @itemx @var{outfile}
1390 The input and output files, respectively.
1391 If you do not specify @var{outfile}, @command{objcopy} creates a
1392 temporary file and destructively renames the result with
1393 the name of @var{infile}.
1394
1395 @item -I @var{bfdname}
1396 @itemx --input-target=@var{bfdname}
1397 Consider the source file's object format to be @var{bfdname}, rather than
1398 attempting to deduce it. @xref{Target Selection}, for more information.
1399
1400 @item -O @var{bfdname}
1401 @itemx --output-target=@var{bfdname}
1402 Write the output file using the object format @var{bfdname}.
1403 @xref{Target Selection}, for more information.
1404
1405 @item -F @var{bfdname}
1406 @itemx --target=@var{bfdname}
1407 Use @var{bfdname} as the object format for both the input and the output
1408 file; i.e., simply transfer data from source to destination with no
1409 translation. @xref{Target Selection}, for more information.
1410
1411 @item -B @var{bfdarch}
1412 @itemx --binary-architecture=@var{bfdarch}
1413 Useful when transforming a architecture-less input file into an object file.
1414 In this case the output architecture can be set to @var{bfdarch}. This
1415 option will be ignored if the input file has a known @var{bfdarch}. You
1416 can access this binary data inside a program by referencing the special
1417 symbols that are created by the conversion process. These symbols are
1418 called _binary_@var{objfile}_start, _binary_@var{objfile}_end and
1419 _binary_@var{objfile}_size. e.g. you can transform a picture file into
1420 an object file and then access it in your code using these symbols.
1421
1422 @item -j @var{sectionpattern}
1423 @itemx --only-section=@var{sectionpattern}
1424 Copy only the indicated sections from the input file to the output file.
1425 This option may be given more than once. Note that using this option
1426 inappropriately may make the output file unusable. Wildcard
1427 characters are accepted in @var{sectionpattern}.
1428
1429 If the first character of @var{sectionpattern} is the exclamation
1430 point (!) then matching sections will not be copied, even if earlier
1431 use of @option{--only-section} on the same command line would
1432 otherwise copy it. For example:
1433
1434 @smallexample
1435 --only-section=.text.* --only-section=!.text.foo
1436 @end smallexample
1437
1438 will copy all sectinos matching '.text.*' but not the section
1439 '.text.foo'.
1440
1441 @item -R @var{sectionpattern}
1442 @itemx --remove-section=@var{sectionpattern}
1443 Remove any section matching @var{sectionpattern} from the output file.
1444 This option may be given more than once. Note that using this option
1445 inappropriately may make the output file unusable. Wildcard
1446 characters are accepted in @var{sectionpattern}. Using both the
1447 @option{-j} and @option{-R} options together results in undefined
1448 behaviour.
1449
1450 If the first character of @var{sectionpattern} is the exclamation
1451 point (!) then matching sections will not be removed even if an
1452 earlier use of @option{--remove-section} on the same command line
1453 would otherwise remove it. For example:
1454
1455 @smallexample
1456 --remove-section=.text.* --remove-section=!.text.foo
1457 @end smallexample
1458
1459 will remove all sections matching the pattern '.text.*', but will not
1460 remove the section '.text.foo'.
1461
1462 @item --keep-section=@var{sectionpattern}
1463 When removing sections from the output file, keep sections that match
1464 @var{sectionpattern}.
1465
1466 @item --remove-relocations=@var{sectionpattern}
1467 Remove non-dynamic relocations from the output file for any section
1468 matching @var{sectionpattern}. This option may be given more than
1469 once. Note that using this option inappropriately may make the output
1470 file unusable, and attempting to remove a dynamic relocation section
1471 such as @samp{.rela.plt} from an executable or shared library with
1472 @option{--remove-relocations=.plt} will not work. Wildcard characters
1473 are accepted in @var{sectionpattern}.
1474 For example:
1475
1476 @smallexample
1477 --remove-relocations=.text.*
1478 @end smallexample
1479
1480 will remove the relocations for all sections matching the pattern
1481 '.text.*'.
1482
1483 If the first character of @var{sectionpattern} is the exclamation
1484 point (!) then matching sections will not have their relocation
1485 removed even if an earlier use of @option{--remove-relocations} on the
1486 same command line would otherwise cause the relocations to be removed.
1487 For example:
1488
1489 @smallexample
1490 --remove-relocations=.text.* --remove-relocations=!.text.foo
1491 @end smallexample
1492
1493 will remove all relocations for sections matching the pattern
1494 '.text.*', but will not remove relocations for the section
1495 '.text.foo'.
1496
1497 @item -S
1498 @itemx --strip-all
1499 Do not copy relocation and symbol information from the source file.
1500 Also deletes debug sections.
1501
1502 @item -g
1503 @itemx --strip-debug
1504 Do not copy debugging symbols or sections from the source file.
1505
1506 @item --strip-unneeded
1507 Remove all symbols that are not needed for relocation processing in
1508 addition to debugging symbols and sections stripped by
1509 @option{--strip-debug}.
1510
1511 @item -K @var{symbolname}
1512 @itemx --keep-symbol=@var{symbolname}
1513 When stripping symbols, keep symbol @var{symbolname} even if it would
1514 normally be stripped. This option may be given more than once.
1515
1516 @item -N @var{symbolname}
1517 @itemx --strip-symbol=@var{symbolname}
1518 Do not copy symbol @var{symbolname} from the source file. This option
1519 may be given more than once.
1520
1521 @item --strip-unneeded-symbol=@var{symbolname}
1522 Do not copy symbol @var{symbolname} from the source file unless it is needed
1523 by a relocation. This option may be given more than once.
1524
1525 @item -G @var{symbolname}
1526 @itemx --keep-global-symbol=@var{symbolname}
1527 Keep only symbol @var{symbolname} global. Make all other symbols local
1528 to the file, so that they are not visible externally. This option may
1529 be given more than once. Note: this option cannot be used in
1530 conjunction with the @option{--globalize-symbol} or
1531 @option{--globalize-symbols} options.
1532
1533 @item --localize-hidden
1534 In an ELF object, mark all symbols that have hidden or internal visibility
1535 as local. This option applies on top of symbol-specific localization options
1536 such as @option{-L}.
1537
1538 @item -L @var{symbolname}
1539 @itemx --localize-symbol=@var{symbolname}
1540 Convert a global or weak symbol called @var{symbolname} into a local
1541 symbol, so that it is not visible externally. This option may be
1542 given more than once. Note - unique symbols are not converted.
1543
1544 @item -W @var{symbolname}
1545 @itemx --weaken-symbol=@var{symbolname}
1546 Make symbol @var{symbolname} weak. This option may be given more than once.
1547
1548 @item --globalize-symbol=@var{symbolname}
1549 Give symbol @var{symbolname} global scoping so that it is visible
1550 outside of the file in which it is defined. This option may be given
1551 more than once. Note: this option cannot be used in conjunction with
1552 the @option{-G} or @option{--keep-global-symbol} options.
1553
1554 @item -w
1555 @itemx --wildcard
1556 Permit regular expressions in @var{symbolname}s used in other command
1557 line options. The question mark (?), asterisk (*), backslash (\) and
1558 square brackets ([]) operators can be used anywhere in the symbol
1559 name. If the first character of the symbol name is the exclamation
1560 point (!) then the sense of the switch is reversed for that symbol.
1561 For example:
1562
1563 @smallexample
1564 -w -W !foo -W fo*
1565 @end smallexample
1566
1567 would cause objcopy to weaken all symbols that start with ``fo''
1568 except for the symbol ``foo''.
1569
1570 @item -x
1571 @itemx --discard-all
1572 Do not copy non-global symbols from the source file.
1573 @c FIXME any reason to prefer "non-global" to "local" here?
1574
1575 @item -X
1576 @itemx --discard-locals
1577 Do not copy compiler-generated local symbols.
1578 (These usually start with @samp{L} or @samp{.}.)
1579
1580 @item -b @var{byte}
1581 @itemx --byte=@var{byte}
1582 If interleaving has been enabled via the @option{--interleave} option
1583 then start the range of bytes to keep at the @var{byte}th byte.
1584 @var{byte} can be in the range from 0 to @var{breadth}-1, where
1585 @var{breadth} is the value given by the @option{--interleave} option.
1586
1587 @item -i [@var{breadth}]
1588 @itemx --interleave[=@var{breadth}]
1589 Only copy a range out of every @var{breadth} bytes. (Header data is
1590 not affected). Select which byte in the range begins the copy with
1591 the @option{--byte} option. Select the width of the range with the
1592 @option{--interleave-width} option.
1593
1594 This option is useful for creating files to program @sc{rom}. It is
1595 typically used with an @code{srec} output target. Note that
1596 @command{objcopy} will complain if you do not specify the
1597 @option{--byte} option as well.
1598
1599 The default interleave breadth is 4, so with @option{--byte} set to 0,
1600 @command{objcopy} would copy the first byte out of every four bytes
1601 from the input to the output.
1602
1603 @item --interleave-width=@var{width}
1604 When used with the @option{--interleave} option, copy @var{width}
1605 bytes at a time. The start of the range of bytes to be copied is set
1606 by the @option{--byte} option, and the extent of the range is set with
1607 the @option{--interleave} option.
1608
1609 The default value for this option is 1. The value of @var{width} plus
1610 the @var{byte} value set by the @option{--byte} option must not exceed
1611 the interleave breadth set by the @option{--interleave} option.
1612
1613 This option can be used to create images for two 16-bit flashes interleaved
1614 in a 32-bit bus by passing @option{-b 0 -i 4 --interleave-width=2}
1615 and @option{-b 2 -i 4 --interleave-width=2} to two @command{objcopy}
1616 commands. If the input was '12345678' then the outputs would be
1617 '1256' and '3478' respectively.
1618
1619 @item -p
1620 @itemx --preserve-dates
1621 Set the access and modification dates of the output file to be the same
1622 as those of the input file.
1623
1624 @item -D
1625 @itemx --enable-deterministic-archives
1626 @cindex deterministic archives
1627 @kindex --enable-deterministic-archives
1628 Operate in @emph{deterministic} mode. When copying archive members
1629 and writing the archive index, use zero for UIDs, GIDs, timestamps,
1630 and use consistent file modes for all files.
1631
1632 If @file{binutils} was configured with
1633 @option{--enable-deterministic-archives}, then this mode is on by default.
1634 It can be disabled with the @samp{-U} option, below.
1635
1636 @item -U
1637 @itemx --disable-deterministic-archives
1638 @cindex deterministic archives
1639 @kindex --enable-deterministic-archives
1640 Do @emph{not} operate in @emph{deterministic} mode. This is the
1641 inverse of the @option{-D} option, above: when copying archive members
1642 and writing the archive index, use their actual UID, GID, timestamp,
1643 and file mode values.
1644
1645 This is the default unless @file{binutils} was configured with
1646 @option{--enable-deterministic-archives}.
1647
1648 @item --debugging
1649 Convert debugging information, if possible. This is not the default
1650 because only certain debugging formats are supported, and the
1651 conversion process can be time consuming.
1652
1653 @item --gap-fill @var{val}
1654 Fill gaps between sections with @var{val}. This operation applies to
1655 the @emph{load address} (LMA) of the sections. It is done by increasing
1656 the size of the section with the lower address, and filling in the extra
1657 space created with @var{val}.
1658
1659 @item --pad-to @var{address}
1660 Pad the output file up to the load address @var{address}. This is
1661 done by increasing the size of the last section. The extra space is
1662 filled in with the value specified by @option{--gap-fill} (default zero).
1663
1664 @item --set-start @var{val}
1665 Set the start address (also known as the entry address) of the new
1666 file to @var{val}. Not all object file formats support setting the
1667 start address.
1668
1669 @item --change-start @var{incr}
1670 @itemx --adjust-start @var{incr}
1671 @cindex changing start address
1672 Change the start address (also known as the entry address) by adding
1673 @var{incr}. Not all object file formats support setting the start
1674 address.
1675
1676 @item --change-addresses @var{incr}
1677 @itemx --adjust-vma @var{incr}
1678 @cindex changing object addresses
1679 Change the VMA and LMA addresses of all sections, as well as the start
1680 address, by adding @var{incr}. Some object file formats do not permit
1681 section addresses to be changed arbitrarily. Note that this does not
1682 relocate the sections; if the program expects sections to be loaded at a
1683 certain address, and this option is used to change the sections such
1684 that they are loaded at a different address, the program may fail.
1685
1686 @item --change-section-address @var{sectionpattern}@{=,+,-@}@var{val}
1687 @itemx --adjust-section-vma @var{sectionpattern}@{=,+,-@}@var{val}
1688 @cindex changing section address
1689 Set or change both the VMA address and the LMA address of any section
1690 matching @var{sectionpattern}. If @samp{=} is used, the section
1691 address is set to @var{val}. Otherwise, @var{val} is added to or
1692 subtracted from the section address. See the comments under
1693 @option{--change-addresses}, above. If @var{sectionpattern} does not
1694 match any sections in the input file, a warning will be issued, unless
1695 @option{--no-change-warnings} is used.
1696
1697 @item --change-section-lma @var{sectionpattern}@{=,+,-@}@var{val}
1698 @cindex changing section LMA
1699 Set or change the LMA address of any sections matching
1700 @var{sectionpattern}. The LMA address is the address where the
1701 section will be loaded into memory at program load time. Normally
1702 this is the same as the VMA address, which is the address of the
1703 section at program run time, but on some systems, especially those
1704 where a program is held in ROM, the two can be different. If @samp{=}
1705 is used, the section address is set to @var{val}. Otherwise,
1706 @var{val} is added to or subtracted from the section address. See the
1707 comments under @option{--change-addresses}, above. If
1708 @var{sectionpattern} does not match any sections in the input file, a
1709 warning will be issued, unless @option{--no-change-warnings} is used.
1710
1711 @item --change-section-vma @var{sectionpattern}@{=,+,-@}@var{val}
1712 @cindex changing section VMA
1713 Set or change the VMA address of any section matching
1714 @var{sectionpattern}. The VMA address is the address where the
1715 section will be located once the program has started executing.
1716 Normally this is the same as the LMA address, which is the address
1717 where the section will be loaded into memory, but on some systems,
1718 especially those where a program is held in ROM, the two can be
1719 different. If @samp{=} is used, the section address is set to
1720 @var{val}. Otherwise, @var{val} is added to or subtracted from the
1721 section address. See the comments under @option{--change-addresses},
1722 above. If @var{sectionpattern} does not match any sections in the
1723 input file, a warning will be issued, unless
1724 @option{--no-change-warnings} is used.
1725
1726 @item --change-warnings
1727 @itemx --adjust-warnings
1728 If @option{--change-section-address} or @option{--change-section-lma} or
1729 @option{--change-section-vma} is used, and the section pattern does not
1730 match any sections, issue a warning. This is the default.
1731
1732 @item --no-change-warnings
1733 @itemx --no-adjust-warnings
1734 Do not issue a warning if @option{--change-section-address} or
1735 @option{--adjust-section-lma} or @option{--adjust-section-vma} is used, even
1736 if the section pattern does not match any sections.
1737
1738 @item --set-section-flags @var{sectionpattern}=@var{flags}
1739 Set the flags for any sections matching @var{sectionpattern}. The
1740 @var{flags} argument is a comma separated string of flag names. The
1741 recognized names are @samp{alloc}, @samp{contents}, @samp{load},
1742 @samp{noload}, @samp{readonly}, @samp{code}, @samp{data}, @samp{rom},
1743 @samp{exclude}, @samp{share}, and @samp{debug}. You can set the
1744 @samp{contents} flag for a section which does not have contents, but it
1745 is not meaningful to clear the @samp{contents} flag of a section which
1746 does have contents--just remove the section instead. Not all flags are
1747 meaningful for all object file formats. In particular the
1748 @samp{share} flag is only meaningful for COFF format files and not for
1749 ELF format files.
1750
1751 @item --set-section-alignment @var{sectionpattern}=@var{align}
1752 Set the alignment for any sections matching @var{sectionpattern}.
1753 @var{align} specifies the alignment in bytes and must be a power of
1754 two, i.e. 1, 2, 4, 8@dots{}.
1755
1756 @item --add-section @var{sectionname}=@var{filename}
1757 Add a new section named @var{sectionname} while copying the file. The
1758 contents of the new section are taken from the file @var{filename}. The
1759 size of the section will be the size of the file. This option only
1760 works on file formats which can support sections with arbitrary names.
1761 Note - it may be necessary to use the @option{--set-section-flags}
1762 option to set the attributes of the newly created section.
1763
1764 @item --dump-section @var{sectionname}=@var{filename}
1765 Place the contents of section named @var{sectionname} into the file
1766 @var{filename}, overwriting any contents that may have been there
1767 previously. This option is the inverse of @option{--add-section}.
1768 This option is similar to the @option{--only-section} option except
1769 that it does not create a formatted file, it just dumps the contents
1770 as raw binary data, without applying any relocations. The option can
1771 be specified more than once.
1772
1773 @item --update-section @var{sectionname}=@var{filename}
1774 Replace the existing contents of a section named @var{sectionname}
1775 with the contents of file @var{filename}. The size of the section
1776 will be adjusted to the size of the file. The section flags for
1777 @var{sectionname} will be unchanged. For ELF format files the section
1778 to segment mapping will also remain unchanged, something which is not
1779 possible using @option{--remove-section} followed by
1780 @option{--add-section}. The option can be specified more than once.
1781
1782 Note - it is possible to use @option{--rename-section} and
1783 @option{--update-section} to both update and rename a section from one
1784 command line. In this case, pass the original section name to
1785 @option{--update-section}, and the original and new section names to
1786 @option{--rename-section}.
1787
1788 @item --add-symbol @var{name}=[@var{section}:]@var{value}[,@var{flags}]
1789 Add a new symbol named @var{name} while copying the file. This option may be
1790 specified multiple times. If the @var{section} is given, the symbol will be
1791 associated with and relative to that section, otherwise it will be an ABS
1792 symbol. Specifying an undefined section will result in a fatal error. There
1793 is no check for the value, it will be taken as specified. Symbol flags can
1794 be specified and not all flags will be meaningful for all object file
1795 formats. By default, the symbol will be global. The special flag
1796 'before=@var{othersym}' will insert the new symbol in front of the specified
1797 @var{othersym}, otherwise the symbol(s) will be added at the end of the
1798 symbol table in the order they appear.
1799
1800 @item --rename-section @var{oldname}=@var{newname}[,@var{flags}]
1801 Rename a section from @var{oldname} to @var{newname}, optionally
1802 changing the section's flags to @var{flags} in the process. This has
1803 the advantage over using a linker script to perform the rename in that
1804 the output stays as an object file and does not become a linked
1805 executable. This option accepts the same set of flags as the
1806 @option{--sect-section-flags} option.
1807
1808 This option is particularly helpful when the input format is binary,
1809 since this will always create a section called .data. If for example,
1810 you wanted instead to create a section called .rodata containing binary
1811 data you could use the following command line to achieve it:
1812
1813 @smallexample
1814 objcopy -I binary -O <output_format> -B <architecture> \
1815 --rename-section .data=.rodata,alloc,load,readonly,data,contents \
1816 <input_binary_file> <output_object_file>
1817 @end smallexample
1818
1819 @item --long-section-names @{enable,disable,keep@}
1820 Controls the handling of long section names when processing @code{COFF}
1821 and @code{PE-COFF} object formats. The default behaviour, @samp{keep},
1822 is to preserve long section names if any are present in the input file.
1823 The @samp{enable} and @samp{disable} options forcibly enable or disable
1824 the use of long section names in the output object; when @samp{disable}
1825 is in effect, any long section names in the input object will be truncated.
1826 The @samp{enable} option will only emit long section names if any are
1827 present in the inputs; this is mostly the same as @samp{keep}, but it
1828 is left undefined whether the @samp{enable} option might force the
1829 creation of an empty string table in the output file.
1830
1831 @item --change-leading-char
1832 Some object file formats use special characters at the start of
1833 symbols. The most common such character is underscore, which compilers
1834 often add before every symbol. This option tells @command{objcopy} to
1835 change the leading character of every symbol when it converts between
1836 object file formats. If the object file formats use the same leading
1837 character, this option has no effect. Otherwise, it will add a
1838 character, or remove a character, or change a character, as
1839 appropriate.
1840
1841 @item --remove-leading-char
1842 If the first character of a global symbol is a special symbol leading
1843 character used by the object file format, remove the character. The
1844 most common symbol leading character is underscore. This option will
1845 remove a leading underscore from all global symbols. This can be useful
1846 if you want to link together objects of different file formats with
1847 different conventions for symbol names. This is different from
1848 @option{--change-leading-char} because it always changes the symbol name
1849 when appropriate, regardless of the object file format of the output
1850 file.
1851
1852 @item --reverse-bytes=@var{num}
1853 Reverse the bytes in a section with output contents. A section length must
1854 be evenly divisible by the value given in order for the swap to be able to
1855 take place. Reversing takes place before the interleaving is performed.
1856
1857 This option is used typically in generating ROM images for problematic
1858 target systems. For example, on some target boards, the 32-bit words
1859 fetched from 8-bit ROMs are re-assembled in little-endian byte order
1860 regardless of the CPU byte order. Depending on the programming model, the
1861 endianness of the ROM may need to be modified.
1862
1863 Consider a simple file with a section containing the following eight
1864 bytes: @code{12345678}.
1865
1866 Using @samp{--reverse-bytes=2} for the above example, the bytes in the
1867 output file would be ordered @code{21436587}.
1868
1869 Using @samp{--reverse-bytes=4} for the above example, the bytes in the
1870 output file would be ordered @code{43218765}.
1871
1872 By using @samp{--reverse-bytes=2} for the above example, followed by
1873 @samp{--reverse-bytes=4} on the output file, the bytes in the second
1874 output file would be ordered @code{34127856}.
1875
1876 @item --srec-len=@var{ival}
1877 Meaningful only for srec output. Set the maximum length of the Srecords
1878 being produced to @var{ival}. This length covers both address, data and
1879 crc fields.
1880
1881 @item --srec-forceS3
1882 Meaningful only for srec output. Avoid generation of S1/S2 records,
1883 creating S3-only record format.
1884
1885 @item --redefine-sym @var{old}=@var{new}
1886 Change the name of a symbol @var{old}, to @var{new}. This can be useful
1887 when one is trying link two things together for which you have no
1888 source, and there are name collisions.
1889
1890 @item --redefine-syms=@var{filename}
1891 Apply @option{--redefine-sym} to each symbol pair "@var{old} @var{new}"
1892 listed in the file @var{filename}. @var{filename} is simply a flat file,
1893 with one symbol pair per line. Line comments may be introduced by the hash
1894 character. This option may be given more than once.
1895
1896 @item --weaken
1897 Change all global symbols in the file to be weak. This can be useful
1898 when building an object which will be linked against other objects using
1899 the @option{-R} option to the linker. This option is only effective when
1900 using an object file format which supports weak symbols.
1901
1902 @item --keep-symbols=@var{filename}
1903 Apply @option{--keep-symbol} option to each symbol listed in the file
1904 @var{filename}. @var{filename} is simply a flat file, with one symbol
1905 name per line. Line comments may be introduced by the hash character.
1906 This option may be given more than once.
1907
1908 @item --strip-symbols=@var{filename}
1909 Apply @option{--strip-symbol} option to each symbol listed in the file
1910 @var{filename}. @var{filename} is simply a flat file, with one symbol
1911 name per line. Line comments may be introduced by the hash character.
1912 This option may be given more than once.
1913
1914 @item --strip-unneeded-symbols=@var{filename}
1915 Apply @option{--strip-unneeded-symbol} option to each symbol listed in
1916 the file @var{filename}. @var{filename} is simply a flat file, with one
1917 symbol name per line. Line comments may be introduced by the hash
1918 character. This option may be given more than once.
1919
1920 @item --keep-global-symbols=@var{filename}
1921 Apply @option{--keep-global-symbol} option to each symbol listed in the
1922 file @var{filename}. @var{filename} is simply a flat file, with one
1923 symbol name per line. Line comments may be introduced by the hash
1924 character. This option may be given more than once.
1925
1926 @item --localize-symbols=@var{filename}
1927 Apply @option{--localize-symbol} option to each symbol listed in the file
1928 @var{filename}. @var{filename} is simply a flat file, with one symbol
1929 name per line. Line comments may be introduced by the hash character.
1930 This option may be given more than once.
1931
1932 @item --globalize-symbols=@var{filename}
1933 Apply @option{--globalize-symbol} option to each symbol listed in the file
1934 @var{filename}. @var{filename} is simply a flat file, with one symbol
1935 name per line. Line comments may be introduced by the hash character.
1936 This option may be given more than once. Note: this option cannot be
1937 used in conjunction with the @option{-G} or @option{--keep-global-symbol}
1938 options.
1939
1940 @item --weaken-symbols=@var{filename}
1941 Apply @option{--weaken-symbol} option to each symbol listed in the file
1942 @var{filename}. @var{filename} is simply a flat file, with one symbol
1943 name per line. Line comments may be introduced by the hash character.
1944 This option may be given more than once.
1945
1946 @item --alt-machine-code=@var{index}
1947 If the output architecture has alternate machine codes, use the
1948 @var{index}th code instead of the default one. This is useful in case
1949 a machine is assigned an official code and the tool-chain adopts the
1950 new code, but other applications still depend on the original code
1951 being used. For ELF based architectures if the @var{index}
1952 alternative does not exist then the value is treated as an absolute
1953 number to be stored in the e_machine field of the ELF header.
1954
1955 @item --writable-text
1956 Mark the output text as writable. This option isn't meaningful for all
1957 object file formats.
1958
1959 @item --readonly-text
1960 Make the output text write protected. This option isn't meaningful for all
1961 object file formats.
1962
1963 @item --pure
1964 Mark the output file as demand paged. This option isn't meaningful for all
1965 object file formats.
1966
1967 @item --impure
1968 Mark the output file as impure. This option isn't meaningful for all
1969 object file formats.
1970
1971 @item --prefix-symbols=@var{string}
1972 Prefix all symbols in the output file with @var{string}.
1973
1974 @item --prefix-sections=@var{string}
1975 Prefix all section names in the output file with @var{string}.
1976
1977 @item --prefix-alloc-sections=@var{string}
1978 Prefix all the names of all allocated sections in the output file with
1979 @var{string}.
1980
1981 @item --add-gnu-debuglink=@var{path-to-file}
1982 Creates a .gnu_debuglink section which contains a reference to
1983 @var{path-to-file} and adds it to the output file. Note: the file at
1984 @var{path-to-file} must exist. Part of the process of adding the
1985 .gnu_debuglink section involves embedding a checksum of the contents
1986 of the debug info file into the section.
1987
1988 If the debug info file is built in one location but it is going to be
1989 installed at a later time into a different location then do not use
1990 the path to the installed location. The @option{--add-gnu-debuglink}
1991 option will fail because the installed file does not exist yet.
1992 Instead put the debug info file in the current directory and use the
1993 @option{--add-gnu-debuglink} option without any directory components,
1994 like this:
1995
1996 @smallexample
1997 objcopy --add-gnu-debuglink=foo.debug
1998 @end smallexample
1999
2000 At debug time the debugger will attempt to look for the separate debug
2001 info file in a set of known locations. The exact set of these
2002 locations varies depending upon the distribution being used, but it
2003 typically includes:
2004
2005 @table @code
2006
2007 @item * The same directory as the executable.
2008
2009 @item * A sub-directory of the directory containing the executable
2010 called .debug
2011
2012 @item * A global debug directory such as /usr/lib/debug.
2013 @end table
2014
2015 As long as the debug info file has been installed into one of these
2016 locations before the debugger is run everything should work
2017 correctly.
2018
2019 @item --keep-section-symbils
2020 When stripping a file, perhaps with @option{--strip-debug} or
2021 @option{--strip-unneeded}, retain any symbols specifying section names,
2022 which would otherwise get stripped.
2023
2024 @item --keep-file-symbols
2025 When stripping a file, perhaps with @option{--strip-debug} or
2026 @option{--strip-unneeded}, retain any symbols specifying source file names,
2027 which would otherwise get stripped.
2028
2029 @item --only-keep-debug
2030 Strip a file, removing contents of any sections that would not be
2031 stripped by @option{--strip-debug} and leaving the debugging sections
2032 intact. In ELF files, this preserves all note sections in the output.
2033
2034 Note - the section headers of the stripped sections are preserved,
2035 including their sizes, but the contents of the section are discarded.
2036 The section headers are preserved so that other tools can match up the
2037 debuginfo file with the real executable, even if that executable has
2038 been relocated to a different address space.
2039
2040 The intention is that this option will be used in conjunction with
2041 @option{--add-gnu-debuglink} to create a two part executable. One a
2042 stripped binary which will occupy less space in RAM and in a
2043 distribution and the second a debugging information file which is only
2044 needed if debugging abilities are required. The suggested procedure
2045 to create these files is as follows:
2046
2047 @enumerate
2048 @item Link the executable as normal. Assuming that it is called
2049 @code{foo} then...
2050 @item Run @code{objcopy --only-keep-debug foo foo.dbg} to
2051 create a file containing the debugging info.
2052 @item Run @code{objcopy --strip-debug foo} to create a
2053 stripped executable.
2054 @item Run @code{objcopy --add-gnu-debuglink=foo.dbg foo}
2055 to add a link to the debugging info into the stripped executable.
2056 @end enumerate
2057
2058 Note---the choice of @code{.dbg} as an extension for the debug info
2059 file is arbitrary. Also the @code{--only-keep-debug} step is
2060 optional. You could instead do this:
2061
2062 @enumerate
2063 @item Link the executable as normal.
2064 @item Copy @code{foo} to @code{foo.full}
2065 @item Run @code{objcopy --strip-debug foo}
2066 @item Run @code{objcopy --add-gnu-debuglink=foo.full foo}
2067 @end enumerate
2068
2069 i.e., the file pointed to by the @option{--add-gnu-debuglink} can be the
2070 full executable. It does not have to be a file created by the
2071 @option{--only-keep-debug} switch.
2072
2073 Note---this switch is only intended for use on fully linked files. It
2074 does not make sense to use it on object files where the debugging
2075 information may be incomplete. Besides the gnu_debuglink feature
2076 currently only supports the presence of one filename containing
2077 debugging information, not multiple filenames on a one-per-object-file
2078 basis.
2079
2080 @item --strip-dwo
2081 Remove the contents of all DWARF .dwo sections, leaving the
2082 remaining debugging sections and all symbols intact.
2083 This option is intended for use by the compiler as part of
2084 the @option{-gsplit-dwarf} option, which splits debug information
2085 between the .o file and a separate .dwo file. The compiler
2086 generates all debug information in the same file, then uses
2087 the @option{--extract-dwo} option to copy the .dwo sections to
2088 the .dwo file, then the @option{--strip-dwo} option to remove
2089 those sections from the original .o file.
2090
2091 @item --extract-dwo
2092 Extract the contents of all DWARF .dwo sections. See the
2093 @option{--strip-dwo} option for more information.
2094
2095 @item --file-alignment @var{num}
2096 Specify the file alignment. Sections in the file will always begin at
2097 file offsets which are multiples of this number. This defaults to
2098 512.
2099 [This option is specific to PE targets.]
2100
2101 @item --heap @var{reserve}
2102 @itemx --heap @var{reserve},@var{commit}
2103 Specify the number of bytes of memory to reserve (and optionally commit)
2104 to be used as heap for this program.
2105 [This option is specific to PE targets.]
2106
2107 @item --image-base @var{value}
2108 Use @var{value} as the base address of your program or dll. This is
2109 the lowest memory location that will be used when your program or dll
2110 is loaded. To reduce the need to relocate and improve performance of
2111 your dlls, each should have a unique base address and not overlap any
2112 other dlls. The default is 0x400000 for executables, and 0x10000000
2113 for dlls.
2114 [This option is specific to PE targets.]
2115
2116 @item --section-alignment @var{num}
2117 Sets the section alignment field in the PE header. Sections in memory
2118 will always begin at addresses which are a multiple of this number.
2119 Defaults to 0x1000.
2120 [This option is specific to PE targets.]
2121
2122 @item --stack @var{reserve}
2123 @itemx --stack @var{reserve},@var{commit}
2124 Specify the number of bytes of memory to reserve (and optionally commit)
2125 to be used as stack for this program.
2126 [This option is specific to PE targets.]
2127
2128 @item --subsystem @var{which}
2129 @itemx --subsystem @var{which}:@var{major}
2130 @itemx --subsystem @var{which}:@var{major}.@var{minor}
2131 Specifies the subsystem under which your program will execute. The
2132 legal values for @var{which} are @code{native}, @code{windows},
2133 @code{console}, @code{posix}, @code{efi-app}, @code{efi-bsd},
2134 @code{efi-rtd}, @code{sal-rtd}, and @code{xbox}. You may optionally set
2135 the subsystem version also. Numeric values are also accepted for
2136 @var{which}.
2137 [This option is specific to PE targets.]
2138
2139 @item --extract-symbol
2140 Keep the file's section flags and symbols but remove all section data.
2141 Specifically, the option:
2142
2143 @itemize
2144 @item removes the contents of all sections;
2145 @item sets the size of every section to zero; and
2146 @item sets the file's start address to zero.
2147 @end itemize
2148
2149 This option is used to build a @file{.sym} file for a VxWorks kernel.
2150 It can also be a useful way of reducing the size of a @option{--just-symbols}
2151 linker input file.
2152
2153 @item --compress-debug-sections
2154 Compress DWARF debug sections using zlib with SHF_COMPRESSED from the
2155 ELF ABI. Note - if compression would actually make a section
2156 @emph{larger}, then it is not compressed.
2157
2158 @item --compress-debug-sections=none
2159 @itemx --compress-debug-sections=zlib
2160 @itemx --compress-debug-sections=zlib-gnu
2161 @itemx --compress-debug-sections=zlib-gabi
2162 @itemx --compress-debug-sections=zstd
2163 For ELF files, these options control how DWARF debug sections are
2164 compressed. @option{--compress-debug-sections=none} is equivalent
2165 to @option{--decompress-debug-sections}.
2166 @option{--compress-debug-sections=zlib} and
2167 @option{--compress-debug-sections=zlib-gabi} are equivalent to
2168 @option{--compress-debug-sections}.
2169 @option{--compress-debug-sections=zlib-gnu} compresses DWARF debug sections
2170 using the obsoleted zlib-gnu format. The debug sections are renamed to begin
2171 with @samp{.zdebug}.
2172 @option{--compress-debug-sections=zstd} compresses DWARF debug
2173 sections using zstd. Note - if compression would actually make a section
2174 @emph{larger}, then it is not compressed nor renamed.
2175
2176 @item --decompress-debug-sections
2177 Decompress DWARF debug sections. For a @samp{.zdebug} section, the original
2178 name is restored.
2179
2180 @item --elf-stt-common=yes
2181 @itemx --elf-stt-common=no
2182 For ELF files, these options control whether common symbols should be
2183 converted to the @code{STT_COMMON} or @code{STT_OBJECT} type.
2184 @option{--elf-stt-common=yes} converts common symbol type to
2185 @code{STT_COMMON}. @option{--elf-stt-common=no} converts common symbol
2186 type to @code{STT_OBJECT}.
2187
2188 @item --merge-notes
2189 @itemx --no-merge-notes
2190 For ELF files, attempt (or do not attempt) to reduce the size of any
2191 SHT_NOTE type sections by removing duplicate notes.
2192
2193 @item -V
2194 @itemx --version
2195 Show the version number of @command{objcopy}.
2196
2197 @item --verilog-data-width=@var{bytes}
2198 For Verilog output, this options controls the number of bytes
2199 converted for each output data element. The input target controls the
2200 endianness of the conversion.
2201
2202 @item -v
2203 @itemx --verbose
2204 Verbose output: list all object files modified. In the case of
2205 archives, @samp{objcopy -V} lists all members of the archive.
2206
2207 @item --help
2208 Show a summary of the options to @command{objcopy}.
2209
2210 @item --info
2211 Display a list showing all architectures and object formats available.
2212 @end table
2213
2214 @c man end
2215
2216 @ignore
2217 @c man begin SEEALSO objcopy
2218 ld(1), objdump(1), and the Info entries for @file{binutils}.
2219 @c man end
2220 @end ignore
2221
2222 @node objdump
2223 @chapter objdump
2224
2225 @cindex object file information
2226 @kindex objdump
2227
2228 @c man title objdump display information from object files
2229
2230 @smallexample
2231 @c man begin SYNOPSIS objdump
2232 objdump [@option{-a}|@option{--archive-headers}]
2233 [@option{-b} @var{bfdname}|@option{--target=@var{bfdname}}]
2234 [@option{-C}|@option{--demangle}[=@var{style}] ]
2235 [@option{-d}|@option{--disassemble}[=@var{symbol}]]
2236 [@option{-D}|@option{--disassemble-all}]
2237 [@option{-z}|@option{--disassemble-zeroes}]
2238 [@option{-EB}|@option{-EL}|@option{--endian=}@{big | little @}]
2239 [@option{-f}|@option{--file-headers}]
2240 [@option{-F}|@option{--file-offsets}]
2241 [@option{--file-start-context}]
2242 [@option{-g}|@option{--debugging}]
2243 [@option{-e}|@option{--debugging-tags}]
2244 [@option{-h}|@option{--section-headers}|@option{--headers}]
2245 [@option{-i}|@option{--info}]
2246 [@option{-j} @var{section}|@option{--section=}@var{section}]
2247 [@option{-l}|@option{--line-numbers}]
2248 [@option{-S}|@option{--source}]
2249 [@option{--source-comment}[=@var{text}]]
2250 [@option{-m} @var{machine}|@option{--architecture=}@var{machine}]
2251 [@option{-M} @var{options}|@option{--disassembler-options=}@var{options}]
2252 [@option{-p}|@option{--private-headers}]
2253 [@option{-P} @var{options}|@option{--private=}@var{options}]
2254 [@option{-r}|@option{--reloc}]
2255 [@option{-R}|@option{--dynamic-reloc}]
2256 [@option{-s}|@option{--full-contents}]
2257 [@option{-W[lLiaprmfFsoORtUuTgAck]}|
2258 @option{--dwarf}[=rawline,=decodedline,=info,=abbrev,=pubnames,=aranges,=macro,=frames,=frames-interp,=str,=str-offsets,=loc,=Ranges,=pubtypes,=trace_info,=trace_abbrev,=trace_aranges,=gdb_index,=addr,=cu_index,=links]]
2259 [@option{-WK}|@option{--dwarf=follow-links}]
2260 [@option{-WN}|@option{--dwarf=no-follow-links}]
2261 [@option{-wD}|@option{--dwarf=use-debuginfod}]
2262 [@option{-wE}|@option{--dwarf=do-not-use-debuginfod}]
2263 [@option{-L}|@option{--process-links}]
2264 [@option{--ctf=}@var{section}]
2265 [@option{-G}|@option{--stabs}]
2266 [@option{-t}|@option{--syms}]
2267 [@option{-T}|@option{--dynamic-syms}]
2268 [@option{-x}|@option{--all-headers}]
2269 [@option{-w}|@option{--wide}]
2270 [@option{--start-address=}@var{address}]
2271 [@option{--stop-address=}@var{address}]
2272 [@option{--no-addresses}]
2273 [@option{--prefix-addresses}]
2274 [@option{--[no-]show-raw-insn}]
2275 [@option{--adjust-vma=}@var{offset}]
2276 [@option{--dwarf-depth=@var{n}}]
2277 [@option{--dwarf-start=@var{n}}]
2278 [@option{--ctf-parent=}@var{section}]
2279 [@option{--no-recurse-limit}|@option{--recurse-limit}]
2280 [@option{--special-syms}]
2281 [@option{--prefix=}@var{prefix}]
2282 [@option{--prefix-strip=}@var{level}]
2283 [@option{--insn-width=}@var{width}]
2284 [@option{--visualize-jumps[=color|=extended-color|=off]}
2285 [@option{--disassembler-color=[color|extended-color|off]}
2286 [@option{-U} @var{method}] [@option{--unicode=}@var{method}]
2287 [@option{-V}|@option{--version}]
2288 [@option{-H}|@option{--help}]
2289 @var{objfile}@dots{}
2290 @c man end
2291 @end smallexample
2292
2293 @c man begin DESCRIPTION objdump
2294
2295 @command{objdump} displays information about one or more object files.
2296 The options control what particular information to display. This
2297 information is mostly useful to programmers who are working on the
2298 compilation tools, as opposed to programmers who just want their
2299 program to compile and work.
2300
2301 @var{objfile}@dots{} are the object files to be examined. When you
2302 specify archives, @command{objdump} shows information on each of the member
2303 object files.
2304
2305 @c man end
2306
2307 @c man begin OPTIONS objdump
2308
2309 The long and short forms of options, shown here as alternatives, are
2310 equivalent. At least one option from the list
2311 @option{-a,-d,-D,-e,-f,-g,-G,-h,-H,-p,-P,-r,-R,-s,-S,-t,-T,-V,-x} must be given.
2312
2313 @table @env
2314 @item -a
2315 @itemx --archive-header
2316 @cindex archive headers
2317 If any of the @var{objfile} files are archives, display the archive
2318 header information (in a format similar to @samp{ls -l}). Besides the
2319 information you could list with @samp{ar tv}, @samp{objdump -a} shows
2320 the object file format of each archive member.
2321
2322 @item --adjust-vma=@var{offset}
2323 @cindex section addresses in objdump
2324 @cindex VMA in objdump
2325 When dumping information, first add @var{offset} to all the section
2326 addresses. This is useful if the section addresses do not correspond to
2327 the symbol table, which can happen when putting sections at particular
2328 addresses when using a format which can not represent section addresses,
2329 such as a.out.
2330
2331 @item -b @var{bfdname}
2332 @itemx --target=@var{bfdname}
2333 @cindex object code format
2334 Specify that the object-code format for the object files is
2335 @var{bfdname}. This option may not be necessary; @var{objdump} can
2336 automatically recognize many formats.
2337
2338 For example,
2339 @example
2340 objdump -b oasys -m vax -h fu.o
2341 @end example
2342 @noindent
2343 displays summary information from the section headers (@option{-h}) of
2344 @file{fu.o}, which is explicitly identified (@option{-m}) as a VAX object
2345 file in the format produced by Oasys compilers. You can list the
2346 formats available with the @option{-i} option.
2347 @xref{Target Selection}, for more information.
2348
2349 @item -C
2350 @itemx --demangle[=@var{style}]
2351 @cindex demangling in objdump
2352 Decode (@dfn{demangle}) low-level symbol names into user-level names.
2353 Besides removing any initial underscore prepended by the system, this
2354 makes C++ function names readable. Different compilers have different
2355 mangling styles. The optional demangling style argument can be used to
2356 choose an appropriate demangling style for your compiler. @xref{c++filt},
2357 for more information on demangling.
2358
2359 @item --recurse-limit
2360 @itemx --no-recurse-limit
2361 @itemx --recursion-limit
2362 @itemx --no-recursion-limit
2363 Enables or disables a limit on the amount of recursion performed
2364 whilst demangling strings. Since the name mangling formats allow for
2365 an infinite level of recursion it is possible to create strings whose
2366 decoding will exhaust the amount of stack space available on the host
2367 machine, triggering a memory fault. The limit tries to prevent this
2368 from happening by restricting recursion to 2048 levels of nesting.
2369
2370 The default is for this limit to be enabled, but disabling it may be
2371 necessary in order to demangle truly complicated names. Note however
2372 that if the recursion limit is disabled then stack exhaustion is
2373 possible and any bug reports about such an event will be rejected.
2374
2375 @item -g
2376 @itemx --debugging
2377 Display debugging information. This attempts to parse STABS
2378 debugging format information stored in the file and print it out using
2379 a C like syntax. If no STABS debugging was found this option
2380 falls back on the @option{-W} option to print any DWARF information in
2381 the file.
2382
2383 @item -e
2384 @itemx --debugging-tags
2385 Like @option{-g}, but the information is generated in a format compatible
2386 with ctags tool.
2387
2388 @item -d
2389 @itemx --disassemble
2390 @itemx --disassemble=@var{symbol}
2391 @cindex disassembling object code
2392 @cindex machine instructions
2393 Display the assembler mnemonics for the machine instructions from the
2394 input file. This option only disassembles those sections which are
2395 expected to contain instructions. If the optional @var{symbol}
2396 argument is given, then display the assembler mnemonics starting at
2397 @var{symbol}. If @var{symbol} is a function name then disassembly
2398 will stop at the end of the function, otherwise it will stop when the
2399 next symbol is encountered. If there are no matches for @var{symbol}
2400 then nothing will be displayed.
2401
2402 Note if the @option{--dwarf=follow-links} option is enabled
2403 then any symbol tables in linked debug info files will be read in and
2404 used when disassembling.
2405
2406 @item -D
2407 @itemx --disassemble-all
2408 Like @option{-d}, but disassemble the contents of all sections, not just
2409 those expected to contain instructions.
2410
2411 This option also has a subtle effect on the disassembly of
2412 instructions in code sections. When option @option{-d} is in effect
2413 objdump will assume that any symbols present in a code section occur
2414 on the boundary between instructions and it will refuse to disassemble
2415 across such a boundary. When option @option{-D} is in effect however
2416 this assumption is supressed. This means that it is possible for the
2417 output of @option{-d} and @option{-D} to differ if, for example, data
2418 is stored in code sections.
2419
2420 If the target is an ARM architecture this switch also has the effect
2421 of forcing the disassembler to decode pieces of data found in code
2422 sections as if they were instructions.
2423
2424 Note if the @option{--dwarf=follow-links} option is enabled
2425 then any symbol tables in linked debug info files will be read in and
2426 used when disassembling.
2427
2428 @item --no-addresses
2429 When disassembling, don't print addresses on each line or for symbols
2430 and relocation offsets. In combination with @option{--no-show-raw-insn}
2431 this may be useful for comparing compiler output.
2432
2433 @item --prefix-addresses
2434 When disassembling, print the complete address on each line. This is
2435 the older disassembly format.
2436
2437 @item -EB
2438 @itemx -EL
2439 @itemx --endian=@{big|little@}
2440 @cindex endianness
2441 @cindex disassembly endianness
2442 Specify the endianness of the object files. This only affects
2443 disassembly. This can be useful when disassembling a file format which
2444 does not describe endianness information, such as S-records.
2445
2446 @item -f
2447 @itemx --file-headers
2448 @cindex object file header
2449 Display summary information from the overall header of
2450 each of the @var{objfile} files.
2451
2452 @item -F
2453 @itemx --file-offsets
2454 @cindex object file offsets
2455 When disassembling sections, whenever a symbol is displayed, also
2456 display the file offset of the region of data that is about to be
2457 dumped. If zeroes are being skipped, then when disassembly resumes,
2458 tell the user how many zeroes were skipped and the file offset of the
2459 location from where the disassembly resumes. When dumping sections,
2460 display the file offset of the location from where the dump starts.
2461
2462 @item --file-start-context
2463 @cindex source code context
2464 Specify that when displaying interlisted source code/disassembly
2465 (assumes @option{-S}) from a file that has not yet been displayed, extend the
2466 context to the start of the file.
2467
2468 @item -h
2469 @itemx --section-headers
2470 @itemx --headers
2471 @cindex section headers
2472 Display summary information from the section headers of the
2473 object file.
2474
2475 File segments may be relocated to nonstandard addresses, for example by
2476 using the @option{-Ttext}, @option{-Tdata}, or @option{-Tbss} options to
2477 @command{ld}. However, some object file formats, such as a.out, do not
2478 store the starting address of the file segments. In those situations,
2479 although @command{ld} relocates the sections correctly, using @samp{objdump
2480 -h} to list the file section headers cannot show the correct addresses.
2481 Instead, it shows the usual addresses, which are implicit for the
2482 target.
2483
2484 Note, in some cases it is possible for a section to have both the
2485 READONLY and the NOREAD attributes set. In such cases the NOREAD
2486 attribute takes precedence, but @command{objdump} will report both
2487 since the exact setting of the flag bits might be important.
2488
2489 @item -H
2490 @itemx --help
2491 Print a summary of the options to @command{objdump} and exit.
2492
2493 @item -i
2494 @itemx --info
2495 @cindex architectures available
2496 @cindex object formats available
2497 Display a list showing all architectures and object formats available
2498 for specification with @option{-b} or @option{-m}.
2499
2500 @item -j @var{name}
2501 @itemx --section=@var{name}
2502 @cindex section information
2503 Display information only for section @var{name}.
2504
2505 @item -L
2506 @itemx --process-links
2507 Display the contents of non-debug sections found in separate debuginfo
2508 files that are linked to the main file. This option automatically
2509 implies the @option{-WK} option, and only sections requested by other
2510 command line options will be displayed.
2511
2512 @item -l
2513 @itemx --line-numbers
2514 @cindex source filenames for object files
2515 Label the display (using debugging information) with the filename and
2516 source line numbers corresponding to the object code or relocs shown.
2517 Only useful with @option{-d}, @option{-D}, or @option{-r}.
2518
2519 @item -m @var{machine}
2520 @itemx --architecture=@var{machine}
2521 @cindex architecture
2522 @cindex disassembly architecture
2523 Specify the architecture to use when disassembling object files. This
2524 can be useful when disassembling object files which do not describe
2525 architecture information, such as S-records. You can list the available
2526 architectures with the @option{-i} option.
2527
2528 If the target is an ARM architecture then this switch has an
2529 additional effect. It restricts the disassembly to only those
2530 instructions supported by the architecture specified by @var{machine}.
2531 If it is necessary to use this switch because the input file does not
2532 contain any architecture information, but it is also desired to
2533 disassemble all the instructions use @option{-marm}.
2534
2535 @item -M @var{options}
2536 @itemx --disassembler-options=@var{options}
2537 Pass target specific information to the disassembler. Only supported on
2538 some targets. If it is necessary to specify more than one
2539 disassembler option then multiple @option{-M} options can be used or
2540 can be placed together into a comma separated list.
2541
2542 For ARC, @option{dsp} controls the printing of DSP instructions,
2543 @option{spfp} selects the printing of FPX single precision FP
2544 instructions, @option{dpfp} selects the printing of FPX double
2545 precision FP instructions, @option{quarkse_em} selects the printing of
2546 special QuarkSE-EM instructions, @option{fpuda} selects the printing
2547 of double precision assist instructions, @option{fpus} selects the
2548 printing of FPU single precision FP instructions, while @option{fpud}
2549 selects the printing of FPU double precision FP instructions.
2550 Additionally, one can choose to have all the immediates printed in
2551 hexadecimal using @option{hex}. By default, the short immediates are
2552 printed using the decimal representation, while the long immediate
2553 values are printed as hexadecimal.
2554
2555 @option{cpu=...} allows one to enforce a particular ISA when disassembling
2556 instructions, overriding the @option{-m} value or whatever is in the ELF file.
2557 This might be useful to select ARC EM or HS ISA, because architecture is same
2558 for those and disassembler relies on private ELF header data to decide if code
2559 is for EM or HS. This option might be specified multiple times - only the
2560 latest value will be used. Valid values are same as for the assembler
2561 @option{-mcpu=...} option.
2562
2563 If the target is an ARM architecture then this switch can be used to
2564 select which register name set is used during disassembler. Specifying
2565 @option{-M reg-names-std} (the default) will select the register names as
2566 used in ARM's instruction set documentation, but with register 13 called
2567 'sp', register 14 called 'lr' and register 15 called 'pc'. Specifying
2568 @option{-M reg-names-apcs} will select the name set used by the ARM
2569 Procedure Call Standard, whilst specifying @option{-M reg-names-raw} will
2570 just use @samp{r} followed by the register number.
2571
2572 There are also two variants on the APCS register naming scheme enabled
2573 by @option{-M reg-names-atpcs} and @option{-M reg-names-special-atpcs} which
2574 use the ARM/Thumb Procedure Call Standard naming conventions. (Either
2575 with the normal register names or the special register names).
2576
2577 This option can also be used for ARM architectures to force the
2578 disassembler to interpret all instructions as Thumb instructions by
2579 using the switch @option{--disassembler-options=force-thumb}. This can be
2580 useful when attempting to disassemble thumb code produced by other
2581 compilers.
2582
2583 For AArch64 targets this switch can be used to set whether instructions are
2584 disassembled as the most general instruction using the @option{-M no-aliases}
2585 option or whether instruction notes should be generated as comments in the
2586 disasssembly using @option{-M notes}.
2587
2588 For the x86, some of the options duplicate functions of the @option{-m}
2589 switch, but allow finer grained control.
2590 @table @code
2591 @item x86-64
2592 @itemx i386
2593 @itemx i8086
2594 Select disassembly for the given architecture.
2595
2596 @item intel
2597 @itemx att
2598 Select between intel syntax mode and AT&T syntax mode.
2599
2600 @item amd64
2601 @itemx intel64
2602 Select between AMD64 ISA and Intel64 ISA.
2603
2604 @item intel-mnemonic
2605 @itemx att-mnemonic
2606 Select between intel mnemonic mode and AT&T mnemonic mode.
2607 Note: @code{intel-mnemonic} implies @code{intel} and
2608 @code{att-mnemonic} implies @code{att}.
2609
2610 @item addr64
2611 @itemx addr32
2612 @itemx addr16
2613 @itemx data32
2614 @itemx data16
2615 Specify the default address size and operand size. These five options
2616 will be overridden if @code{x86-64}, @code{i386} or @code{i8086}
2617 appear later in the option string.
2618
2619 @item suffix
2620 When in AT&T mode and also for a limited set of instructions when in Intel
2621 mode, instructs the disassembler to print a mnemonic suffix even when the
2622 suffix could be inferred by the operands or, for certain instructions, the
2623 execution mode's defaults.
2624 @end table
2625
2626 For PowerPC, the @option{-M} argument @option{raw} selects
2627 disasssembly of hardware insns rather than aliases. For example, you
2628 will see @code{rlwinm} rather than @code{clrlwi}, and @code{addi}
2629 rather than @code{li}. All of the @option{-m} arguments for
2630 @command{gas} that select a CPU are supported. These are:
2631 @option{403}, @option{405}, @option{440}, @option{464}, @option{476},
2632 @option{601}, @option{603}, @option{604}, @option{620}, @option{7400},
2633 @option{7410}, @option{7450}, @option{7455}, @option{750cl},
2634 @option{821}, @option{850}, @option{860}, @option{a2}, @option{booke},
2635 @option{booke32}, @option{cell}, @option{com}, @option{e200z2}, @option{e200z4},
2636 @option{e300}, @option{e500}, @option{e500mc}, @option{e500mc64},
2637 @option{e500x2}, @option{e5500}, @option{e6500}, @option{efs},
2638 @option{power4}, @option{power5}, @option{power6}, @option{power7},
2639 @option{power8}, @option{power9}, @option{power10}, @option{ppc},
2640 @option{ppc32}, @option{ppc64}, @option{ppc64bridge}, @option{ppcps},
2641 @option{pwr}, @option{pwr2}, @option{pwr4}, @option{pwr5}, @option{pwr5x},
2642 @option{pwr6}, @option{pwr7}, @option{pwr8}, @option{pwr9}, @option{pwr10},
2643 @option{pwrx}, @option{titan}, @option{vle}, and @option{future}.
2644 @option{32} and @option{64} modify the default or a prior CPU
2645 selection, disabling and enabling 64-bit insns respectively. In
2646 addition, @option{altivec}, @option{any}, @option{lsp}, @option{htm},
2647 @option{vsx}, @option{spe} and @option{spe2} add capabilities to a
2648 previous @emph{or later} CPU selection.
2649 @option{any} will disassemble any opcode known to
2650 binutils, but in cases where an opcode has two different meanings or
2651 different arguments, you may not see the disassembly you expect.
2652 If you disassemble without giving a CPU selection, a default will be
2653 chosen from information gleaned by BFD from the object files headers,
2654 but the result again may not be as you expect.
2655
2656 For MIPS, this option controls the printing of instruction mnemonic
2657 names and register names in disassembled instructions. Multiple
2658 selections from the following may be specified as a comma separated
2659 string, and invalid options are ignored:
2660
2661 @table @code
2662 @item no-aliases
2663 Print the 'raw' instruction mnemonic instead of some pseudo
2664 instruction mnemonic. I.e., print 'daddu' or 'or' instead of 'move',
2665 'sll' instead of 'nop', etc.
2666
2667 @item msa
2668 Disassemble MSA instructions.
2669
2670 @item virt
2671 Disassemble the virtualization ASE instructions.
2672
2673 @item xpa
2674 Disassemble the eXtended Physical Address (XPA) ASE instructions.
2675
2676 @item gpr-names=@var{ABI}
2677 Print GPR (general-purpose register) names as appropriate
2678 for the specified ABI. By default, GPR names are selected according to
2679 the ABI of the binary being disassembled.
2680
2681 @item fpr-names=@var{ABI}
2682 Print FPR (floating-point register) names as
2683 appropriate for the specified ABI. By default, FPR numbers are printed
2684 rather than names.
2685
2686 @item cp0-names=@var{ARCH}
2687 Print CP0 (system control coprocessor; coprocessor 0) register names
2688 as appropriate for the CPU or architecture specified by
2689 @var{ARCH}. By default, CP0 register names are selected according to
2690 the architecture and CPU of the binary being disassembled.
2691
2692 @item hwr-names=@var{ARCH}
2693 Print HWR (hardware register, used by the @code{rdhwr} instruction) names
2694 as appropriate for the CPU or architecture specified by
2695 @var{ARCH}. By default, HWR names are selected according to
2696 the architecture and CPU of the binary being disassembled.
2697
2698 @item reg-names=@var{ABI}
2699 Print GPR and FPR names as appropriate for the selected ABI.
2700
2701 @item reg-names=@var{ARCH}
2702 Print CPU-specific register names (CP0 register and HWR names)
2703 as appropriate for the selected CPU or architecture.
2704 @end table
2705
2706 For any of the options listed above, @var{ABI} or
2707 @var{ARCH} may be specified as @samp{numeric} to have numbers printed
2708 rather than names, for the selected types of registers.
2709 You can list the available values of @var{ABI} and @var{ARCH} using
2710 the @option{--help} option.
2711
2712 For VAX, you can specify function entry addresses with @option{-M
2713 entry:0xf00ba}. You can use this multiple times to properly
2714 disassemble VAX binary files that don't contain symbol tables (like
2715 ROM dumps). In these cases, the function entry mask would otherwise
2716 be decoded as VAX instructions, which would probably lead the rest
2717 of the function being wrongly disassembled.
2718
2719 @item -p
2720 @itemx --private-headers
2721 Print information that is specific to the object file format. The exact
2722 information printed depends upon the object file format. For some
2723 object file formats, no additional information is printed.
2724
2725 @item -P @var{options}
2726 @itemx --private=@var{options}
2727 Print information that is specific to the object file format. The
2728 argument @var{options} is a comma separated list that depends on the
2729 format (the lists of options is displayed with the help).
2730
2731 For XCOFF, the available options are:
2732 @table @code
2733 @item header
2734 @item aout
2735 @item sections
2736 @item syms
2737 @item relocs
2738 @item lineno,
2739 @item loader
2740 @item except
2741 @item typchk
2742 @item traceback
2743 @item toc
2744 @item ldinfo
2745 @end table
2746
2747 Not all object formats support this option. In particular the ELF
2748 format does not use it.
2749
2750 @item -r
2751 @itemx --reloc
2752 @cindex relocation entries, in object file
2753 Print the relocation entries of the file. If used with @option{-d} or
2754 @option{-D}, the relocations are printed interspersed with the
2755 disassembly.
2756
2757 @item -R
2758 @itemx --dynamic-reloc
2759 @cindex dynamic relocation entries, in object file
2760 Print the dynamic relocation entries of the file. This is only
2761 meaningful for dynamic objects, such as certain types of shared
2762 libraries. As for @option{-r}, if used with @option{-d} or
2763 @option{-D}, the relocations are printed interspersed with the
2764 disassembly.
2765
2766 @item -s
2767 @itemx --full-contents
2768 @cindex sections, full contents
2769 @cindex object file sections
2770 Display the full contents of any sections requested. By default all
2771 non-empty sections are displayed.
2772
2773 @item -S
2774 @itemx --source
2775 @cindex source disassembly
2776 @cindex disassembly, with source
2777 Display source code intermixed with disassembly, if possible. Implies
2778 @option{-d}.
2779
2780 @item --source-comment[=@var{txt}]
2781 @cindex source disassembly
2782 @cindex disassembly, with source
2783 Like the @option{-S} option, but all source code lines are displayed
2784 with a prefix of @var{txt}. Typically @var{txt} will be a comment
2785 string which can be used to distinguish the assembler code from the
2786 source code. If @var{txt} is not provided then a default string of
2787 @var{``# ``} (hash followed by a space), will be used.
2788
2789 @item --prefix=@var{prefix}
2790 @cindex Add prefix to absolute paths
2791 Specify @var{prefix} to add to the absolute paths when used with
2792 @option{-S}.
2793
2794 @item --prefix-strip=@var{level}
2795 @cindex Strip absolute paths
2796 Indicate how many initial directory names to strip off the hardwired
2797 absolute paths. It has no effect without @option{--prefix=}@var{prefix}.
2798
2799 @item --show-raw-insn
2800 When disassembling instructions, print the instruction in hex as well as
2801 in symbolic form. This is the default except when
2802 @option{--prefix-addresses} is used.
2803
2804 @item --no-show-raw-insn
2805 When disassembling instructions, do not print the instruction bytes.
2806 This is the default when @option{--prefix-addresses} is used.
2807
2808 @item --insn-width=@var{width}
2809 @cindex Instruction width
2810 Display @var{width} bytes on a single line when disassembling
2811 instructions.
2812
2813 @item --visualize-jumps[=color|=extended-color|=off]
2814 Visualize jumps that stay inside a function by drawing ASCII art between
2815 the start and target addresses. The optional @option{=color} argument
2816 adds color to the output using simple terminal colors. Alternatively
2817 the @option{=extended-color} argument will add color using 8bit
2818 colors, but these might not work on all terminals.
2819
2820 If it is necessary to disable the @option{visualize-jumps} option
2821 after it has previously been enabled then use
2822 @option{visualize-jumps=off}.
2823
2824 @item --disassembler-color=[color|extended-color|off]
2825 Apply syntax highlighting to the disassembler output. The
2826 @option{color} argument adds color using simple terminal colors.
2827 Alternatively the @option{extended-color} argument will use 8bit
2828 colors, but these might not work on all terminals.
2829
2830 If it is necessary to disable the @option{--disassembler-color} option
2831 after it has previously been enabled then use
2832 @option{--disassembler-color=off}.
2833
2834 If this option is not specified then the default is to enable color
2835 output if displaying to a terminal, but not otherwise.
2836
2837 @item -W[lLiaprmfFsoORtUuTgAckK]
2838 @itemx --dwarf[=rawline,=decodedline,=info,=abbrev,=pubnames,=aranges,=macro,=frames,=frames-interp,=str,=str-offsets,=loc,=Ranges,=pubtypes,=trace_info,=trace_abbrev,=trace_aranges,=gdb_index,=addr,=cu_index,=links,=follow-links]
2839 @include debug.options.texi
2840
2841 @item --dwarf-check
2842 Enable additional checks for consistency of Dwarf information.
2843
2844 @include ctf.options.texi
2845
2846 @item -G
2847 @itemx --stabs
2848 @cindex stab
2849 @cindex .stab
2850 @cindex debug symbols
2851 @cindex ELF object file format
2852 Display the full contents of any sections requested. Display the
2853 contents of the .stab and .stab.index and .stab.excl sections from an
2854 ELF file. This is only useful on systems (such as Solaris 2.0) in which
2855 @code{.stab} debugging symbol-table entries are carried in an ELF
2856 section. In most other file formats, debugging symbol-table entries are
2857 interleaved with linkage symbols, and are visible in the @option{--syms}
2858 output.
2859
2860 @item --start-address=@var{address}
2861 @cindex start-address
2862 Start displaying data at the specified address. This affects the output
2863 of the @option{-d}, @option{-r} and @option{-s} options.
2864
2865 @item --stop-address=@var{address}
2866 @cindex stop-address
2867 Stop displaying data at the specified address. This affects the output
2868 of the @option{-d}, @option{-r} and @option{-s} options.
2869
2870 @item -t
2871 @itemx --syms
2872 @cindex symbol table entries, printing
2873 Print the symbol table entries of the file.
2874 This is similar to the information provided by the @samp{nm} program,
2875 although the display format is different. The format of the output
2876 depends upon the format of the file being dumped, but there are two main
2877 types. One looks like this:
2878
2879 @smallexample
2880 [ 4](sec 3)(fl 0x00)(ty 0)(scl 3) (nx 1) 0x00000000 .bss
2881 [ 6](sec 1)(fl 0x00)(ty 0)(scl 2) (nx 0) 0x00000000 fred
2882 @end smallexample
2883
2884 where the number inside the square brackets is the number of the entry
2885 in the symbol table, the @var{sec} number is the section number, the
2886 @var{fl} value are the symbol's flag bits, the @var{ty} number is the
2887 symbol's type, the @var{scl} number is the symbol's storage class and
2888 the @var{nx} value is the number of auxiliary entries associated with
2889 the symbol. The last two fields are the symbol's value and its name.
2890
2891 The other common output format, usually seen with ELF based files,
2892 looks like this:
2893
2894 @smallexample
2895 00000000 l d .bss 00000000 .bss
2896 00000000 g .text 00000000 fred
2897 @end smallexample
2898
2899 Here the first number is the symbol's value (sometimes referred to as
2900 its address). The next field is actually a set of characters and
2901 spaces indicating the flag bits that are set on the symbol. These
2902 characters are described below. Next is the section with which the
2903 symbol is associated or @emph{*ABS*} if the section is absolute (ie
2904 not connected with any section), or @emph{*UND*} if the section is
2905 referenced in the file being dumped, but not defined there.
2906
2907 After the section name comes another field, a number, which for common
2908 symbols is the alignment and for other symbol is the size. Finally
2909 the symbol's name is displayed.
2910
2911 The flag characters are divided into 7 groups as follows:
2912 @table @code
2913 @item l
2914 @itemx g
2915 @itemx u
2916 @itemx !
2917 The symbol is a local (l), global (g), unique global (u), neither
2918 global nor local (a space) or both global and local (!). A
2919 symbol can be neither local or global for a variety of reasons, e.g.,
2920 because it is used for debugging, but it is probably an indication of
2921 a bug if it is ever both local and global. Unique global symbols are
2922 a GNU extension to the standard set of ELF symbol bindings. For such
2923 a symbol the dynamic linker will make sure that in the entire process
2924 there is just one symbol with this name and type in use.
2925
2926 @item w
2927 The symbol is weak (w) or strong (a space).
2928
2929 @item C
2930 The symbol denotes a constructor (C) or an ordinary symbol (a space).
2931
2932 @item W
2933 The symbol is a warning (W) or a normal symbol (a space). A warning
2934 symbol's name is a message to be displayed if the symbol following the
2935 warning symbol is ever referenced.
2936
2937 @item I
2938 @item i
2939 The symbol is an indirect reference to another symbol (I), a function
2940 to be evaluated during reloc processing (i) or a normal symbol (a
2941 space).
2942
2943 @item d
2944 @itemx D
2945 The symbol is a debugging symbol (d) or a dynamic symbol (D) or a
2946 normal symbol (a space).
2947
2948 @item F
2949 @item f
2950 @item O
2951 The symbol is the name of a function (F) or a file (f) or an object
2952 (O) or just a normal symbol (a space).
2953 @end table
2954
2955 @item -T
2956 @itemx --dynamic-syms
2957 @cindex dynamic symbol table entries, printing
2958 Print the dynamic symbol table entries of the file. This is only
2959 meaningful for dynamic objects, such as certain types of shared
2960 libraries. This is similar to the information provided by the @samp{nm}
2961 program when given the @option{-D} (@option{--dynamic}) option.
2962
2963 The output format is similar to that produced by the @option{--syms}
2964 option, except that an extra field is inserted before the symbol's
2965 name, giving the version information associated with the symbol.
2966 If the version is the default version to be used when resolving
2967 unversioned references to the symbol then it's displayed as is,
2968 otherwise it's put into parentheses.
2969
2970 @item --special-syms
2971 When displaying symbols include those which the target considers to be
2972 special in some way and which would not normally be of interest to the
2973 user.
2974
2975 @item -U @var{[d|i|l|e|x|h]}
2976 @itemx --unicode=@var{[default|invalid|locale|escape|hex|highlight]}
2977 Controls the display of UTF-8 encoded multibyte characters in strings.
2978 The default (@option{--unicode=default}) is to give them no special
2979 treatment. The @option{--unicode=locale} option displays the sequence
2980 in the current locale, which may or may not support them. The options
2981 @option{--unicode=hex} and @option{--unicode=invalid} display them as
2982 hex byte sequences enclosed by either angle brackets or curly braces.
2983
2984 The @option{--unicode=escape} option displays them as escape sequences
2985 (@var{\uxxxx}) and the @option{--unicode=highlight} option displays
2986 them as escape sequences highlighted in red (if supported by the
2987 output device). The colouring is intended to draw attention to the
2988 presence of unicode sequences where they might not be expected.
2989
2990 @item -V
2991 @itemx --version
2992 Print the version number of @command{objdump} and exit.
2993
2994 @item -x
2995 @itemx --all-headers
2996 @cindex all header information, object file
2997 @cindex header information, all
2998 Display all available header information, including the symbol table and
2999 relocation entries. Using @option{-x} is equivalent to specifying all of
3000 @option{-a -f -h -p -r -t}.
3001
3002 @item -w
3003 @itemx --wide
3004 @cindex wide output, printing
3005 Format some lines for output devices that have more than 80 columns.
3006 Also do not truncate symbol names when they are displayed.
3007
3008 @item -z
3009 @itemx --disassemble-zeroes
3010 Normally the disassembly output will skip blocks of zeroes. This
3011 option directs the disassembler to disassemble those blocks, just like
3012 any other data.
3013 @end table
3014
3015 @c man end
3016
3017 @ignore
3018 @c man begin SEEALSO objdump
3019 nm(1), readelf(1), and the Info entries for @file{binutils}.
3020 @c man end
3021 @end ignore
3022
3023 @node ranlib
3024 @chapter ranlib
3025
3026 @kindex ranlib
3027 @cindex archive contents
3028 @cindex symbol index
3029
3030 @c man title ranlib generate an index to an archive
3031
3032 @smallexample
3033 @c man begin SYNOPSIS ranlib
3034 ranlib [@option{--plugin} @var{name}] [@option{-DhHvVt}] @var{archive}
3035 @c man end
3036 @end smallexample
3037
3038 @c man begin DESCRIPTION ranlib
3039
3040 @command{ranlib} generates an index to the contents of an archive and
3041 stores it in the archive. The index lists each symbol defined by a
3042 member of an archive that is a relocatable object file.
3043
3044 You may use @samp{nm -s} or @samp{nm --print-armap} to list this index.
3045
3046 An archive with such an index speeds up linking to the library and
3047 allows routines in the library to call each other without regard to
3048 their placement in the archive.
3049
3050 The @sc{gnu} @command{ranlib} program is another form of @sc{gnu} @command{ar}; running
3051 @command{ranlib} is completely equivalent to executing @samp{ar -s}.
3052 @xref{ar}.
3053
3054 @c man end
3055
3056 @c man begin OPTIONS ranlib
3057
3058 @table @env
3059 @item -h
3060 @itemx -H
3061 @itemx --help
3062 Show usage information for @command{ranlib}.
3063
3064 @item -v
3065 @itemx -V
3066 @itemx --version
3067 Show the version number of @command{ranlib}.
3068
3069 @item -D
3070 @cindex deterministic archives
3071 @kindex --enable-deterministic-archives
3072 Operate in @emph{deterministic} mode. The symbol map archive member's
3073 header will show zero for the UID, GID, and timestamp. When this
3074 option is used, multiple runs will produce identical output files.
3075
3076 If @file{binutils} was configured with
3077 @option{--enable-deterministic-archives}, then this mode is on by
3078 default. It can be disabled with the @samp{-U} option, described
3079 below.
3080
3081 @item -t
3082 Update the timestamp of the symbol map of an archive.
3083
3084 @item -U
3085 @cindex deterministic archives
3086 @kindex --enable-deterministic-archives
3087 Do @emph{not} operate in @emph{deterministic} mode. This is the
3088 inverse of the @samp{-D} option, above: the archive index will get
3089 actual UID, GID, timestamp, and file mode values.
3090
3091 If @file{binutils} was configured @emph{without}
3092 @option{--enable-deterministic-archives}, then this mode is on by
3093 default.
3094
3095 @end table
3096
3097 @c man end
3098
3099 @ignore
3100 @c man begin SEEALSO ranlib
3101 ar(1), nm(1), and the Info entries for @file{binutils}.
3102 @c man end
3103 @end ignore
3104
3105 @node size
3106 @chapter size
3107
3108 @kindex size
3109 @cindex section sizes
3110
3111 @c man title size list section sizes and total size of binary files
3112
3113 @smallexample
3114 @c man begin SYNOPSIS size
3115 size [@option{-A}|@option{-B}|@option{-G}|@option{--format=}@var{compatibility}]
3116 [@option{--help}]
3117 [@option{-d}|@option{-o}|@option{-x}|@option{--radix=}@var{number}]
3118 [@option{--common}]
3119 [@option{-t}|@option{--totals}]
3120 [@option{--target=}@var{bfdname}] [@option{-V}|@option{--version}]
3121 [@option{-f}]
3122 [@var{objfile}@dots{}]
3123 @c man end
3124 @end smallexample
3125
3126 @c man begin DESCRIPTION size
3127
3128 The @sc{gnu} @command{size} utility lists the section sizes and the total
3129 size for each of the binary files @var{objfile} on its argument list.
3130 By default, one line of output is generated for each file or each
3131 module if the file is an archive.
3132
3133 @var{objfile}@dots{} are the files to be examined. If none are
3134 specified, the file @code{a.out} will be used instead.
3135
3136 @c man end
3137
3138 @c man begin OPTIONS size
3139
3140 The command-line options have the following meanings:
3141
3142 @table @env
3143 @item -A
3144 @itemx -B
3145 @itemx -G
3146 @itemx --format=@var{compatibility}
3147 @cindex @command{size} display format
3148 Using one of these options, you can choose whether the output from @sc{gnu}
3149 @command{size} resembles output from System V @command{size} (using @option{-A},
3150 or @option{--format=sysv}), or Berkeley @command{size} (using @option{-B}, or
3151 @option{--format=berkeley}). The default is the one-line format similar to
3152 Berkeley's. Alternatively, you can choose the GNU format output
3153 (using @option{-G}, or @option{--format=gnu}), this is similar to
3154 Berkeley's output format, but sizes are counted differently.
3155 @c Bonus for doc-source readers: you can also say --format=strange (or
3156 @c anything else that starts with 's') for sysv, and --format=boring (or
3157 @c anything else that starts with 'b') for Berkeley.
3158
3159 Here is an example of the Berkeley (default) format of output from
3160 @command{size}:
3161 @smallexample
3162 $ size --format=Berkeley ranlib size
3163 text data bss dec hex filename
3164 294880 81920 11592 388392 5ed28 ranlib
3165 294880 81920 11888 388688 5ee50 size
3166 @end smallexample
3167
3168 The Berkeley style output counts read only data in the @code{text}
3169 column, not in the @code{data} column, the @code{dec} and @code{hex}
3170 columns both display the sum of the @code{text}, @code{data}, and
3171 @code{bss} columns in decimal and hexadecimal respectively.
3172
3173 The GNU format counts read only data in the @code{data} column, not
3174 the @code{text} column, and only displays the sum of the @code{text},
3175 @code{data}, and @code{bss} columns once, in the @code{total} column.
3176 The @option{--radix} option can be used to change the number base for
3177 all columns. Here is the same data displayed with GNU conventions:
3178
3179 @smallexample
3180 $ size --format=GNU ranlib size
3181 text data bss total filename
3182 279880 96920 11592 388392 ranlib
3183 279880 96920 11888 388688 size
3184 @end smallexample
3185
3186 @noindent
3187 This is the same data, but displayed closer to System V conventions:
3188
3189 @smallexample
3190 $ size --format=SysV ranlib size
3191 ranlib :
3192 section size addr
3193 .text 294880 8192
3194 .data 81920 303104
3195 .bss 11592 385024
3196 Total 388392
3197
3198
3199 size :
3200 section size addr
3201 .text 294880 8192
3202 .data 81920 303104
3203 .bss 11888 385024
3204 Total 388688
3205 @end smallexample
3206
3207 @item --help
3208 @itemx -h
3209 @itemx -H
3210 @item -?
3211 Show a summary of acceptable arguments and options.
3212
3213 @item -d
3214 @itemx -o
3215 @itemx -x
3216 @itemx --radix=@var{number}
3217 @cindex @command{size} number format
3218 @cindex radix for section sizes
3219 Using one of these options, you can control whether the size of each
3220 section is given in decimal (@option{-d}, or @option{--radix=10}); octal
3221 (@option{-o}, or @option{--radix=8}); or hexadecimal (@option{-x}, or
3222 @option{--radix=16}). In @option{--radix=@var{number}}, only the three
3223 values (8, 10, 16) are supported. The total size is always given in two
3224 radices; decimal and hexadecimal for @option{-d} or @option{-x} output, or
3225 octal and hexadecimal if you're using @option{-o}.
3226
3227 @item --common
3228 Print total size of common symbols in each file. When using Berkeley
3229 or GNU format these are included in the bss size.
3230
3231 @item -t
3232 @itemx --totals
3233 Show totals of all objects listed (Berkeley or GNU format mode only).
3234
3235 @item --target=@var{bfdname}
3236 @cindex object code format
3237 Specify that the object-code format for @var{objfile} is
3238 @var{bfdname}. This option may not be necessary; @command{size} can
3239 automatically recognize many formats.
3240 @xref{Target Selection}, for more information.
3241
3242 @item -v
3243 @item -V
3244 @itemx --version
3245 Display the version number of @command{size}.
3246
3247 @item -f
3248 Ignored. This option is used by other versions of the @command{size}
3249 program, but it is not supported by the GNU Binutils version.
3250
3251 @end table
3252
3253 @c man end
3254
3255 @ignore
3256 @c man begin SEEALSO size
3257 ar(1), objdump(1), readelf(1), and the Info entries for @file{binutils}.
3258 @c man end
3259 @end ignore
3260
3261 @node strings
3262 @chapter strings
3263 @kindex strings
3264 @cindex listings strings
3265 @cindex printing strings
3266 @cindex strings, printing
3267
3268 @c man title strings print the sequences of printable characters in files
3269
3270 @smallexample
3271 @c man begin SYNOPSIS strings
3272 strings [@option{-afovV}] [@option{-}@var{min-len}]
3273 [@option{-n} @var{min-len}] [@option{--bytes=}@var{min-len}]
3274 [@option{-t} @var{radix}] [@option{--radix=}@var{radix}]
3275 [@option{-e} @var{encoding}] [@option{--encoding=}@var{encoding}]
3276 [@option{-U} @var{method}] [@option{--unicode=}@var{method}]
3277 [@option{-}] [@option{--all}] [@option{--print-file-name}]
3278 [@option{-T} @var{bfdname}] [@option{--target=}@var{bfdname}]
3279 [@option{-w}] [@option{--include-all-whitespace}]
3280 [@option{-s}] [@option{--output-separator} @var{sep_string}]
3281 [@option{--help}] [@option{--version}] @var{file}@dots{}
3282 @c man end
3283 @end smallexample
3284
3285 @c man begin DESCRIPTION strings
3286
3287 For each @var{file} given, @sc{gnu} @command{strings} prints the
3288 printable character sequences that are at least 4 characters long (or
3289 the number given with the options below) and are followed by an
3290 unprintable character.
3291
3292 Depending upon how the strings program was configured it will default
3293 to either displaying all the printable sequences that it can find in
3294 each file, or only those sequences that are in loadable, initialized
3295 data sections. If the file type is unrecognizable, or if strings is
3296 reading from stdin then it will always display all of the printable
3297 sequences that it can find.
3298
3299 For backwards compatibility any file that occurs after a command-line
3300 option of just @option{-} will also be scanned in full, regardless of
3301 the presence of any @option{-d} option.
3302
3303 @command{strings} is mainly useful for determining the contents of
3304 non-text files.
3305
3306 @c man end
3307
3308 @c man begin OPTIONS strings
3309
3310 @table @env
3311 @item -a
3312 @itemx --all
3313 @itemx -
3314 Scan the whole file, regardless of what sections it contains or
3315 whether those sections are loaded or initialized. Normally this is
3316 the default behaviour, but strings can be configured so that the
3317 @option{-d} is the default instead.
3318
3319 The @option{-} option is position dependent and forces strings to
3320 perform full scans of any file that is mentioned after the @option{-}
3321 on the command line, even if the @option{-d} option has been
3322 specified.
3323
3324 @item -d
3325 @itemx --data
3326 Only print strings from initialized, loaded data sections in the
3327 file. This may reduce the amount of garbage in the output, but it
3328 also exposes the strings program to any security flaws that may be
3329 present in the BFD library used to scan and load sections. Strings
3330 can be configured so that this option is the default behaviour. In
3331 such cases the @option{-a} option can be used to avoid using the BFD
3332 library and instead just print all of the strings found in the file.
3333
3334 @item -f
3335 @itemx --print-file-name
3336 Print the name of the file before each string.
3337
3338 @item --help
3339 Print a summary of the program usage on the standard output and exit.
3340
3341 @item -@var{min-len}
3342 @itemx -n @var{min-len}
3343 @itemx --bytes=@var{min-len}
3344 Print sequences of displayable characters that are at least
3345 @var{min-len} characters long. If not specified a default minimum
3346 length of 4 is used. The distinction between displayable and
3347 non-displayable characters depends upon the setting of the
3348 @option{-e} and @option{-U} options. Sequences are always terminated
3349 at control characters such as new-line and carriage-return, but not
3350 the tab character.
3351
3352 @item -o
3353 Like @samp{-t o}. Some other versions of @command{strings} have @option{-o}
3354 act like @samp{-t d} instead. Since we can not be compatible with both
3355 ways, we simply chose one.
3356
3357 @item -t @var{radix}
3358 @itemx --radix=@var{radix}
3359 Print the offset within the file before each string. The single
3360 character argument specifies the radix of the offset---@samp{o} for
3361 octal, @samp{x} for hexadecimal, or @samp{d} for decimal.
3362
3363 @item -e @var{encoding}
3364 @itemx --encoding=@var{encoding}
3365 Select the character encoding of the strings that are to be found.
3366 Possible values for @var{encoding} are: @samp{s} = single-7-bit-byte
3367 characters (ASCII, ISO 8859, etc., default), @samp{S} =
3368 single-8-bit-byte characters, @samp{b} = 16-bit bigendian, @samp{l} =
3369 16-bit littleendian, @samp{B} = 32-bit bigendian, @samp{L} = 32-bit
3370 littleendian. Useful for finding wide character strings. (@samp{l}
3371 and @samp{b} apply to, for example, Unicode UTF-16/UCS-2 encodings).
3372
3373 @item -U @var{[d|i|l|e|x|h]}
3374 @itemx --unicode=@var{[default|invalid|locale|escape|hex|highlight]}
3375 Controls the display of UTF-8 encoded multibyte characters in strings.
3376 The default (@option{--unicode=default}) is to give them no special
3377 treatment, and instead rely upon the setting of the
3378 @option{--encoding} option. The other values for this option
3379 automatically enable @option{--encoding=S}.
3380
3381 The @option{--unicode=invalid} option treats them as non-graphic
3382 characters and hence not part of a valid string. All the remaining
3383 options treat them as valid string characters.
3384
3385 The @option{--unicode=locale} option displays them in the current
3386 locale, which may or may not support UTF-8 encoding. The
3387 @option{--unicode=hex} option displays them as hex byte sequences
3388 enclosed between @var{<>} characters. The @option{--unicode=escape}
3389 option displays them as escape sequences (@var{\uxxxx}) and the
3390 @option{--unicode=highlight} option displays them as escape sequences
3391 highlighted in red (if supported by the output device). The colouring
3392 is intended to draw attention to the presence of unicode sequences
3393 where they might not be expected.
3394
3395 @item -T @var{bfdname}
3396 @itemx --target=@var{bfdname}
3397 @cindex object code format
3398 Specify an object code format other than your system's default format.
3399 @xref{Target Selection}, for more information.
3400
3401 @item -v
3402 @itemx -V
3403 @itemx --version
3404 Print the program version number on the standard output and exit.
3405
3406 @item -w
3407 @itemx --include-all-whitespace
3408 By default tab and space characters are included in the strings that
3409 are displayed, but other whitespace characters, such a newlines and
3410 carriage returns, are not. The @option{-w} option changes this so
3411 that all whitespace characters are considered to be part of a string.
3412
3413 @item -s
3414 @itemx --output-separator
3415 By default, output strings are delimited by a new-line. This option
3416 allows you to supply any string to be used as the output record
3417 separator. Useful with --include-all-whitespace where strings
3418 may contain new-lines internally.
3419 @end table
3420
3421 @c man end
3422
3423 @ignore
3424 @c man begin SEEALSO strings
3425 ar(1), nm(1), objdump(1), ranlib(1), readelf(1)
3426 and the Info entries for @file{binutils}.
3427 @c man end
3428 @end ignore
3429
3430 @node strip
3431 @chapter strip
3432
3433 @kindex strip
3434 @cindex removing symbols
3435 @cindex discarding symbols
3436 @cindex symbols, discarding
3437
3438 @c man title strip discard symbols and other data from object files
3439
3440 @smallexample
3441 @c man begin SYNOPSIS strip
3442 strip [@option{-F} @var{bfdname} |@option{--target=}@var{bfdname}]
3443 [@option{-I} @var{bfdname} |@option{--input-target=}@var{bfdname}]
3444 [@option{-O} @var{bfdname} |@option{--output-target=}@var{bfdname}]
3445 [@option{-s}|@option{--strip-all}]
3446 [@option{-S}|@option{-g}|@option{-d}|@option{--strip-debug}]
3447 [@option{--strip-dwo}]
3448 [@option{-K} @var{symbolname}|@option{--keep-symbol=}@var{symbolname}]
3449 [@option{-M}|@option{--merge-notes}][@option{--no-merge-notes}]
3450 [@option{-N} @var{symbolname} |@option{--strip-symbol=}@var{symbolname}]
3451 [@option{-w}|@option{--wildcard}]
3452 [@option{-x}|@option{--discard-all}] [@option{-X} |@option{--discard-locals}]
3453 [@option{-R} @var{sectionname} |@option{--remove-section=}@var{sectionname}]
3454 [@option{--keep-section=}@var{sectionpattern}]
3455 [@option{--remove-relocations=}@var{sectionpattern}]
3456 [@option{-o} @var{file}] [@option{-p}|@option{--preserve-dates}]
3457 [@option{-D}|@option{--enable-deterministic-archives}]
3458 [@option{-U}|@option{--disable-deterministic-archives}]
3459 [@option{--keep-section-symbols}]
3460 [@option{--keep-file-symbols}]
3461 [@option{--only-keep-debug}]
3462 [@option{-v} |@option{--verbose}] [@option{-V}|@option{--version}]
3463 [@option{--help}] [@option{--info}]
3464 @var{objfile}@dots{}
3465 @c man end
3466 @end smallexample
3467
3468 @c man begin DESCRIPTION strip
3469
3470 @sc{gnu} @command{strip} discards all symbols from object files
3471 @var{objfile}. The list of object files may include archives.
3472 At least one object file must be given.
3473
3474 @command{strip} modifies the files named in its argument,
3475 rather than writing modified copies under different names.
3476
3477 @c man end
3478
3479 @c man begin OPTIONS strip
3480
3481 @table @env
3482 @item -F @var{bfdname}
3483 @itemx --target=@var{bfdname}
3484 Treat the original @var{objfile} as a file with the object
3485 code format @var{bfdname}, and rewrite it in the same format.
3486 @xref{Target Selection}, for more information.
3487
3488 @item --help
3489 Show a summary of the options to @command{strip} and exit.
3490
3491 @item --info
3492 Display a list showing all architectures and object formats available.
3493
3494 @item -I @var{bfdname}
3495 @itemx --input-target=@var{bfdname}
3496 Treat the original @var{objfile} as a file with the object
3497 code format @var{bfdname}.
3498 @xref{Target Selection}, for more information.
3499
3500 @item -O @var{bfdname}
3501 @itemx --output-target=@var{bfdname}
3502 Replace @var{objfile} with a file in the output format @var{bfdname}.
3503 @xref{Target Selection}, for more information.
3504
3505 @item -R @var{sectionname}
3506 @itemx --remove-section=@var{sectionname}
3507 Remove any section named @var{sectionname} from the output file, in
3508 addition to whatever sections would otherwise be removed. This
3509 option may be given more than once. Note that using this option
3510 inappropriately may make the output file unusable. The wildcard
3511 character @samp{*} may be given at the end of @var{sectionname}. If
3512 so, then any section starting with @var{sectionname} will be removed.
3513
3514 If the first character of @var{sectionpattern} is the exclamation
3515 point (!) then matching sections will not be removed even if an
3516 earlier use of @option{--remove-section} on the same command line
3517 would otherwise remove it. For example:
3518
3519 @smallexample
3520 --remove-section=.text.* --remove-section=!.text.foo
3521 @end smallexample
3522
3523 will remove all sections matching the pattern '.text.*', but will not
3524 remove the section '.text.foo'.
3525
3526 @item --keep-section=@var{sectionpattern}
3527 When removing sections from the output file, keep sections that match
3528 @var{sectionpattern}.
3529
3530 @item --remove-relocations=@var{sectionpattern}
3531 Remove relocations from the output file for any section matching
3532 @var{sectionpattern}. This option may be given more than once. Note
3533 that using this option inappropriately may make the output file
3534 unusable. Wildcard characters are accepted in @var{sectionpattern}.
3535 For example:
3536
3537 @smallexample
3538 --remove-relocations=.text.*
3539 @end smallexample
3540
3541 will remove the relocations for all sections matching the patter
3542 '.text.*'.
3543
3544 If the first character of @var{sectionpattern} is the exclamation
3545 point (!) then matching sections will not have their relocation
3546 removed even if an earlier use of @option{--remove-relocations} on the
3547 same command line would otherwise cause the relocations to be removed.
3548 For example:
3549
3550 @smallexample
3551 --remove-relocations=.text.* --remove-relocations=!.text.foo
3552 @end smallexample
3553
3554 will remove all relocations for sections matching the pattern
3555 '.text.*', but will not remove relocations for the section
3556 '.text.foo'.
3557
3558 @item -s
3559 @itemx --strip-all
3560 Remove all symbols.
3561
3562 @item -g
3563 @itemx -S
3564 @itemx -d
3565 @itemx --strip-debug
3566 Remove debugging symbols only.
3567
3568 @item --strip-dwo
3569 Remove the contents of all DWARF .dwo sections, leaving the
3570 remaining debugging sections and all symbols intact.
3571 See the description of this option in the @command{objcopy} section
3572 for more information.
3573
3574 @item --strip-unneeded
3575 Remove all symbols that are not needed for relocation processing in
3576 addition to debugging symbols and sections stripped by
3577 @option{--strip-debug}.
3578
3579 @item -K @var{symbolname}
3580 @itemx --keep-symbol=@var{symbolname}
3581 When stripping symbols, keep symbol @var{symbolname} even if it would
3582 normally be stripped. This option may be given more than once.
3583
3584 @item -M
3585 @itemx --merge-notes
3586 @itemx --no-merge-notes
3587 For ELF files, attempt (or do not attempt) to reduce the size of any
3588 SHT_NOTE type sections by removing duplicate notes. The default is to
3589 attempt this reduction unless stripping debug or DWO information.
3590
3591 @item -N @var{symbolname}
3592 @itemx --strip-symbol=@var{symbolname}
3593 Remove symbol @var{symbolname} from the source file. This option may be
3594 given more than once, and may be combined with strip options other than
3595 @option{-K}.
3596
3597 @item -o @var{file}
3598 Put the stripped output in @var{file}, rather than replacing the
3599 existing file. When this argument is used, only one @var{objfile}
3600 argument may be specified.
3601
3602 @item -p
3603 @itemx --preserve-dates
3604 Preserve the access and modification dates of the file.
3605
3606 @item -D
3607 @itemx --enable-deterministic-archives
3608 @cindex deterministic archives
3609 @kindex --enable-deterministic-archives
3610 Operate in @emph{deterministic} mode. When copying archive members
3611 and writing the archive index, use zero for UIDs, GIDs, timestamps,
3612 and use consistent file modes for all files.
3613
3614 If @file{binutils} was configured with
3615 @option{--enable-deterministic-archives}, then this mode is on by default.
3616 It can be disabled with the @samp{-U} option, below.
3617
3618 @item -U
3619 @itemx --disable-deterministic-archives
3620 @cindex deterministic archives
3621 @kindex --enable-deterministic-archives
3622 Do @emph{not} operate in @emph{deterministic} mode. This is the
3623 inverse of the @option{-D} option, above: when copying archive members
3624 and writing the archive index, use their actual UID, GID, timestamp,
3625 and file mode values.
3626
3627 This is the default unless @file{binutils} was configured with
3628 @option{--enable-deterministic-archives}.
3629
3630 @item -w
3631 @itemx --wildcard
3632 Permit regular expressions in @var{symbolname}s used in other command
3633 line options. The question mark (?), asterisk (*), backslash (\) and
3634 square brackets ([]) operators can be used anywhere in the symbol
3635 name. If the first character of the symbol name is the exclamation
3636 point (!) then the sense of the switch is reversed for that symbol.
3637 For example:
3638
3639 @smallexample
3640 -w -K !foo -K fo*
3641 @end smallexample
3642
3643 would cause strip to only keep symbols that start with the letters
3644 ``fo'', but to discard the symbol ``foo''.
3645
3646 @item -x
3647 @itemx --discard-all
3648 Remove non-global symbols.
3649
3650 @item -X
3651 @itemx --discard-locals
3652 Remove compiler-generated local symbols.
3653 (These usually start with @samp{L} or @samp{.}.)
3654
3655 @item --keep-section-symbols
3656 When stripping a file, perhaps with @option{--strip-debug} or
3657 @option{--strip-unneeded}, retain any symbols specifying section names,
3658 which would otherwise get stripped.
3659
3660 @item --keep-file-symbols
3661 When stripping a file, perhaps with @option{--strip-debug} or
3662 @option{--strip-unneeded}, retain any symbols specifying source file names,
3663 which would otherwise get stripped.
3664
3665 @item --only-keep-debug
3666 Strip a file, emptying the contents of any sections that would not be
3667 stripped by @option{--strip-debug} and leaving the debugging sections
3668 intact. In ELF files, this preserves all the note sections in the
3669 output as well.
3670
3671 Note - the section headers of the stripped sections are preserved,
3672 including their sizes, but the contents of the section are discarded.
3673 The section headers are preserved so that other tools can match up the
3674 debuginfo file with the real executable, even if that executable has
3675 been relocated to a different address space.
3676
3677 The intention is that this option will be used in conjunction with
3678 @option{--add-gnu-debuglink} to create a two part executable. One a
3679 stripped binary which will occupy less space in RAM and in a
3680 distribution and the second a debugging information file which is only
3681 needed if debugging abilities are required. The suggested procedure
3682 to create these files is as follows:
3683
3684 @enumerate
3685 @item Link the executable as normal. Assuming that it is called
3686 @code{foo} then...
3687 @item Run @code{objcopy --only-keep-debug foo foo.dbg} to
3688 create a file containing the debugging info.
3689 @item Run @code{objcopy --strip-debug foo} to create a
3690 stripped executable.
3691 @item Run @code{objcopy --add-gnu-debuglink=foo.dbg foo}
3692 to add a link to the debugging info into the stripped executable.
3693 @end enumerate
3694
3695 Note---the choice of @code{.dbg} as an extension for the debug info
3696 file is arbitrary. Also the @code{--only-keep-debug} step is
3697 optional. You could instead do this:
3698
3699 @enumerate
3700 @item Link the executable as normal.
3701 @item Copy @code{foo} to @code{foo.full}
3702 @item Run @code{strip --strip-debug foo}
3703 @item Run @code{objcopy --add-gnu-debuglink=foo.full foo}
3704 @end enumerate
3705
3706 i.e., the file pointed to by the @option{--add-gnu-debuglink} can be the
3707 full executable. It does not have to be a file created by the
3708 @option{--only-keep-debug} switch.
3709
3710 Note---this switch is only intended for use on fully linked files. It
3711 does not make sense to use it on object files where the debugging
3712 information may be incomplete. Besides the gnu_debuglink feature
3713 currently only supports the presence of one filename containing
3714 debugging information, not multiple filenames on a one-per-object-file
3715 basis.
3716
3717 @item -V
3718 @itemx --version
3719 Show the version number for @command{strip}.
3720
3721 @item -v
3722 @itemx --verbose
3723 Verbose output: list all object files modified. In the case of
3724 archives, @samp{strip -v} lists all members of the archive.
3725 @end table
3726
3727 @c man end
3728
3729 @ignore
3730 @c man begin SEEALSO strip
3731 the Info entries for @file{binutils}.
3732 @c man end
3733 @end ignore
3734
3735 @node c++filt, addr2line, strip, Top
3736 @chapter c++filt
3737
3738 @kindex c++filt
3739 @cindex demangling C++ symbols
3740
3741 @c man title cxxfilt demangle C++ and Java symbols
3742
3743 @smallexample
3744 @c man begin SYNOPSIS cxxfilt
3745 c++filt [@option{-_}|@option{--strip-underscore}]
3746 [@option{-n}|@option{--no-strip-underscore}]
3747 [@option{-p}|@option{--no-params}]
3748 [@option{-t}|@option{--types}]
3749 [@option{-i}|@option{--no-verbose}]
3750 [@option{-r}|@option{--no-recurse-limit}]
3751 [@option{-R}|@option{--recurse-limit}]
3752 [@option{-s} @var{format}|@option{--format=}@var{format}]
3753 [@option{--help}] [@option{--version}] [@var{symbol}@dots{}]
3754 @c man end
3755 @end smallexample
3756
3757 @c man begin DESCRIPTION cxxfilt
3758
3759 @kindex cxxfilt
3760 The C++ and Java languages provide function overloading, which means
3761 that you can write many functions with the same name, providing that
3762 each function takes parameters of different types. In order to be
3763 able to distinguish these similarly named functions C++ and Java
3764 encode them into a low-level assembler name which uniquely identifies
3765 each different version. This process is known as @dfn{mangling}. The
3766 @command{c++filt}
3767 @footnote{MS-DOS does not allow @kbd{+} characters in file names, so on
3768 MS-DOS this program is named @command{CXXFILT}.}
3769 program does the inverse mapping: it decodes (@dfn{demangles}) low-level
3770 names into user-level names so that they can be read.
3771
3772 Every alphanumeric word (consisting of letters, digits, underscores,
3773 dollars, or periods) seen in the input is a potential mangled name.
3774 If the name decodes into a C++ name, the C++ name replaces the
3775 low-level name in the output, otherwise the original word is output.
3776 In this way you can pass an entire assembler source file, containing
3777 mangled names, through @command{c++filt} and see the same source file
3778 containing demangled names.
3779
3780 You can also use @command{c++filt} to decipher individual symbols by
3781 passing them on the command line:
3782
3783 @example
3784 c++filt @var{symbol}
3785 @end example
3786
3787 If no @var{symbol} arguments are given, @command{c++filt} reads symbol
3788 names from the standard input instead. All the results are printed on
3789 the standard output. The difference between reading names from the
3790 command line versus reading names from the standard input is that
3791 command-line arguments are expected to be just mangled names and no
3792 checking is performed to separate them from surrounding text. Thus
3793 for example:
3794
3795 @smallexample
3796 c++filt -n _Z1fv
3797 @end smallexample
3798
3799 will work and demangle the name to ``f()'' whereas:
3800
3801 @smallexample
3802 c++filt -n _Z1fv,
3803 @end smallexample
3804
3805 will not work. (Note the extra comma at the end of the mangled
3806 name which makes it invalid). This command however will work:
3807
3808 @smallexample
3809 echo _Z1fv, | c++filt -n
3810 @end smallexample
3811
3812 and will display ``f(),'', i.e., the demangled name followed by a
3813 trailing comma. This behaviour is because when the names are read
3814 from the standard input it is expected that they might be part of an
3815 assembler source file where there might be extra, extraneous
3816 characters trailing after a mangled name. For example:
3817
3818 @smallexample
3819 .type _Z1fv, @@function
3820 @end smallexample
3821
3822 @c man end
3823
3824 @c man begin OPTIONS cxxfilt
3825
3826 @table @env
3827 @item -_
3828 @itemx --strip-underscore
3829 On some systems, both the C and C++ compilers put an underscore in front
3830 of every name. For example, the C name @code{foo} gets the low-level
3831 name @code{_foo}. This option removes the initial underscore. Whether
3832 @command{c++filt} removes the underscore by default is target dependent.
3833
3834 @item -n
3835 @itemx --no-strip-underscore
3836 Do not remove the initial underscore.
3837
3838 @item -p
3839 @itemx --no-params
3840 When demangling the name of a function, do not display the types of
3841 the function's parameters.
3842
3843 @item -t
3844 @itemx --types
3845 Attempt to demangle types as well as function names. This is disabled
3846 by default since mangled types are normally only used internally in
3847 the compiler, and they can be confused with non-mangled names. For example,
3848 a function called ``a'' treated as a mangled type name would be
3849 demangled to ``signed char''.
3850
3851 @item -i
3852 @itemx --no-verbose
3853 Do not include implementation details (if any) in the demangled
3854 output.
3855
3856 @item -r
3857 @itemx -R
3858 @itemx --recurse-limit
3859 @itemx --no-recurse-limit
3860 @itemx --recursion-limit
3861 @itemx --no-recursion-limit
3862 Enables or disables a limit on the amount of recursion performed
3863 whilst demangling strings. Since the name mangling formats allow for
3864 an infinite level of recursion it is possible to create strings whose
3865 decoding will exhaust the amount of stack space available on the host
3866 machine, triggering a memory fault. The limit tries to prevent this
3867 from happening by restricting recursion to 2048 levels of nesting.
3868
3869 The default is for this limit to be enabled, but disabling it may be
3870 necessary in order to demangle truly complicated names. Note however
3871 that if the recursion limit is disabled then stack exhaustion is
3872 possible and any bug reports about such an event will be rejected.
3873
3874 The @option{-r} option is a synonym for the
3875 @option{--no-recurse-limit} option. The @option{-R} option is a
3876 synonym for the @option{--recurse-limit} option.
3877
3878 @item -s @var{format}
3879 @itemx --format=@var{format}
3880 @command{c++filt} can decode various methods of mangling, used by
3881 different compilers. The argument to this option selects which
3882 method it uses:
3883
3884 @table @code
3885 @item auto
3886 Automatic selection based on executable (the default method)
3887 @item gnu
3888 the one used by the @sc{gnu} C++ compiler (g++)
3889 @item lucid
3890 the one used by the Lucid compiler (lcc)
3891 @item arm
3892 the one specified by the C++ Annotated Reference Manual
3893 @item hp
3894 the one used by the HP compiler (aCC)
3895 @item edg
3896 the one used by the EDG compiler
3897 @item gnu-v3
3898 the one used by the @sc{gnu} C++ compiler (g++) with the V3 ABI.
3899 @item java
3900 the one used by the @sc{gnu} Java compiler (gcj)
3901 @item gnat
3902 the one used by the @sc{gnu} Ada compiler (GNAT).
3903 @end table
3904
3905 @item --help
3906 Print a summary of the options to @command{c++filt} and exit.
3907
3908 @item --version
3909 Print the version number of @command{c++filt} and exit.
3910 @end table
3911
3912 @c man end
3913
3914 @ignore
3915 @c man begin SEEALSO cxxfilt
3916 the Info entries for @file{binutils}.
3917 @c man end
3918 @end ignore
3919
3920 @quotation
3921 @emph{Warning:} @command{c++filt} is a new utility, and the details of its
3922 user interface are subject to change in future releases. In particular,
3923 a command-line option may be required in the future to decode a name
3924 passed as an argument on the command line; in other words,
3925
3926 @example
3927 c++filt @var{symbol}
3928 @end example
3929
3930 @noindent
3931 may in a future release become
3932
3933 @example
3934 c++filt @var{option} @var{symbol}
3935 @end example
3936 @end quotation
3937
3938 @node addr2line
3939 @chapter addr2line
3940
3941 @kindex addr2line
3942 @cindex address to file name and line number
3943
3944 @c man title addr2line convert addresses or symbol+offset into file names and line numbers
3945
3946 @smallexample
3947 @c man begin SYNOPSIS addr2line
3948 addr2line [@option{-a}|@option{--addresses}]
3949 [@option{-b} @var{bfdname}|@option{--target=}@var{bfdname}]
3950 [@option{-C}|@option{--demangle}[=@var{style}]]
3951 [@option{-r}|@option{--no-recurse-limit}]
3952 [@option{-R}|@option{--recurse-limit}]
3953 [@option{-e} @var{filename}|@option{--exe=}@var{filename}]
3954 [@option{-f}|@option{--functions}] [@option{-s}|@option{--basename}]
3955 [@option{-i}|@option{--inlines}]
3956 [@option{-p}|@option{--pretty-print}]
3957 [@option{-j}|@option{--section=}@var{name}]
3958 [@option{-H}|@option{--help}] [@option{-V}|@option{--version}]
3959 [addr addr @dots{}]
3960 @c man end
3961 @end smallexample
3962
3963 @c man begin DESCRIPTION addr2line
3964
3965 @command{addr2line} translates addresses or symbol+offset into file names and line numbers.
3966 Given an address or symbol+offset in an executable or an offset in a section of a relocatable
3967 object, it uses the debugging information to figure out which file name and
3968 line number are associated with it.
3969
3970 The executable or relocatable object to use is specified with the @option{-e}
3971 option. The default is the file @file{a.out}. The section in the relocatable
3972 object to use is specified with the @option{-j} option.
3973
3974 @command{addr2line} has two modes of operation.
3975
3976 In the first, hexadecimal addresses or symbol+offset are specified on the command line,
3977 and @command{addr2line} displays the file name and line number for each
3978 address.
3979
3980 In the second, @command{addr2line} reads hexadecimal addresses or symbol+offset from
3981 standard input, and prints the file name and line number for each
3982 address on standard output. In this mode, @command{addr2line} may be used
3983 in a pipe to convert dynamically chosen addresses.
3984
3985 The format of the output is @samp{FILENAME:LINENO}. By default
3986 each input address generates one line of output.
3987
3988 Two options can generate additional lines before each
3989 @samp{FILENAME:LINENO} line (in that order).
3990
3991 If the @option{-a} option is used then a line with the input address
3992 is displayed.
3993
3994 If the @option{-f} option is used, then a line with the
3995 @samp{FUNCTIONNAME} is displayed. This is the name of the function
3996 containing the address.
3997
3998 One option can generate additional lines after the
3999 @samp{FILENAME:LINENO} line.
4000
4001 If the @option{-i} option is used and the code at the given address is
4002 present there because of inlining by the compiler then additional
4003 lines are displayed afterwards. One or two extra lines (if the
4004 @option{-f} option is used) are displayed for each inlined function.
4005
4006 Alternatively if the @option{-p} option is used then each input
4007 address generates a single, long, output line containing the address,
4008 the function name, the file name and the line number. If the
4009 @option{-i} option has also been used then any inlined functions will
4010 be displayed in the same manner, but on separate lines, and prefixed
4011 by the text @samp{(inlined by)}.
4012
4013 If the file name or function name can not be determined,
4014 @command{addr2line} will print two question marks in their place. If the
4015 line number can not be determined, @command{addr2line} will print 0.
4016
4017 When symbol+offset is used, +offset is optional, except when the symbol
4018 is ambigious with a hex number. The resolved symbols can be mangled
4019 or unmangled, except unmangled symbols with + are not allowed.
4020
4021 @c man end
4022
4023 @c man begin OPTIONS addr2line
4024
4025 The long and short forms of options, shown here as alternatives, are
4026 equivalent.
4027
4028 @table @env
4029 @item -a
4030 @itemx --addresses
4031 Display the address before the function name, file and line number
4032 information. The address is printed with a @samp{0x} prefix to easily
4033 identify it.
4034
4035 @item -b @var{bfdname}
4036 @itemx --target=@var{bfdname}
4037 @cindex object code format
4038 Specify that the object-code format for the object files is
4039 @var{bfdname}.
4040
4041 @item -C
4042 @itemx --demangle[=@var{style}]
4043 @cindex demangling in objdump
4044 Decode (@dfn{demangle}) low-level symbol names into user-level names.
4045 Besides removing any initial underscore prepended by the system, this
4046 makes C++ function names readable. Different compilers have different
4047 mangling styles. The optional demangling style argument can be used to
4048 choose an appropriate demangling style for your compiler. @xref{c++filt},
4049 for more information on demangling.
4050
4051 @item -e @var{filename}
4052 @itemx --exe=@var{filename}
4053 Specify the name of the executable for which addresses should be
4054 translated. The default file is @file{a.out}.
4055
4056 @item -f
4057 @itemx --functions
4058 Display function names as well as file and line number information.
4059
4060 @item -s
4061 @itemx --basenames
4062 Display only the base of each file name.
4063
4064 @item -i
4065 @itemx --inlines
4066 If the address belongs to a function that was inlined, the source
4067 information for all enclosing scopes back to the first non-inlined
4068 function will also be printed. For example, if @code{main} inlines
4069 @code{callee1} which inlines @code{callee2}, and address is from
4070 @code{callee2}, the source information for @code{callee1} and @code{main}
4071 will also be printed.
4072
4073 @item -j
4074 @itemx --section
4075 Read offsets relative to the specified section instead of absolute addresses.
4076
4077 @item -p
4078 @itemx --pretty-print
4079 Make the output more human friendly: each location are printed on one line.
4080 If option @option{-i} is specified, lines for all enclosing scopes are
4081 prefixed with @samp{(inlined by)}.
4082
4083 @item -r
4084 @itemx -R
4085 @itemx --recurse-limit
4086 @itemx --no-recurse-limit
4087 @itemx --recursion-limit
4088 @itemx --no-recursion-limit
4089 Enables or disables a limit on the amount of recursion performed
4090 whilst demangling strings. Since the name mangling formats allow for
4091 an infinite level of recursion it is possible to create strings whose
4092 decoding will exhaust the amount of stack space available on the host
4093 machine, triggering a memory fault. The limit tries to prevent this
4094 from happening by restricting recursion to 2048 levels of nesting.
4095
4096 The default is for this limit to be enabled, but disabling it may be
4097 necessary in order to demangle truly complicated names. Note however
4098 that if the recursion limit is disabled then stack exhaustion is
4099 possible and any bug reports about such an event will be rejected.
4100
4101 The @option{-r} option is a synonym for the
4102 @option{--no-recurse-limit} option. The @option{-R} option is a
4103 synonym for the @option{--recurse-limit} option.
4104
4105 Note this option is only effective if the @option{-C} or
4106 @option{--demangle} option has been enabled.
4107
4108 @end table
4109
4110 @c man end
4111
4112 @ignore
4113 @c man begin SEEALSO addr2line
4114 Info entries for @file{binutils}.
4115 @c man end
4116 @end ignore
4117
4118 @node windmc
4119 @chapter windmc
4120
4121 @command{windmc} may be used to generator Windows message resources.
4122
4123 @quotation
4124 @emph{Warning:} @command{windmc} is not always built as part of the binary
4125 utilities, since it is only useful for Windows targets.
4126 @end quotation
4127
4128 @c man title windmc generates Windows message resources
4129
4130 @smallexample
4131 @c man begin SYNOPSIS windmc
4132 windmc [options] input-file
4133 @c man end
4134 @end smallexample
4135
4136 @c man begin DESCRIPTION windmc
4137
4138 @command{windmc} reads message definitions from an input file (.mc) and
4139 translate them into a set of output files. The output files may be of
4140 four kinds:
4141
4142 @table @code
4143 @item h
4144 A C header file containing the message definitions.
4145
4146 @item rc
4147 A resource file compilable by the @command{windres} tool.
4148
4149 @item bin
4150 One or more binary files containing the resource data for a specific
4151 message language.
4152
4153 @item dbg
4154 A C include file that maps message id's to their symbolic name.
4155 @end table
4156
4157 The exact description of these different formats is available in
4158 documentation from Microsoft.
4159
4160 When @command{windmc} converts from the @code{mc} format to the @code{bin}
4161 format, @code{rc}, @code{h}, and optional @code{dbg} it is acting like the
4162 Windows Message Compiler.
4163
4164 @c man end
4165
4166 @c man begin OPTIONS windmc
4167
4168 @table @env
4169 @item -a
4170 @itemx --ascii_in
4171 Specifies that the input file specified is ASCII. This is the default
4172 behaviour.
4173
4174 @item -A
4175 @itemx --ascii_out
4176 Specifies that messages in the output @code{bin} files should be in ASCII
4177 format.
4178
4179 @item -b
4180 @itemx --binprefix
4181 Specifies that @code{bin} filenames should have to be prefixed by the
4182 basename of the source file.
4183
4184 @item -c
4185 @itemx --customflag
4186 Sets the customer bit in all message id's.
4187
4188 @item -C @var{codepage}
4189 @itemx --codepage_in @var{codepage}
4190 Sets the default codepage to be used to convert input file to UTF16. The
4191 default is ocdepage 1252.
4192
4193 @item -d
4194 @itemx --decimal_values
4195 Outputs the constants in the header file in decimal. Default is using
4196 hexadecimal output.
4197
4198 @item -e @var{ext}
4199 @itemx --extension @var{ext}
4200 The extension for the header file. The default is .h extension.
4201
4202 @item -F @var{target}
4203 @itemx --target @var{target}
4204 Specify the BFD format to use for a bin file as output. This
4205 is a BFD target name; you can use the @option{--help} option to see a list
4206 of supported targets. Normally @command{windmc} will use the default
4207 format, which is the first one listed by the @option{--help} option.
4208 @ifclear man
4209 @ref{Target Selection}.
4210 @end ifclear
4211
4212 @item -h @var{path}
4213 @itemx --headerdir @var{path}
4214 The target directory of the generated header file. The default is the
4215 current directory.
4216
4217 @item -H
4218 @itemx --help
4219 Displays a list of command-line options and then exits.
4220
4221 @item -m @var{characters}
4222 @itemx --maxlength @var{characters}
4223 Instructs @command{windmc} to generate a warning if the length
4224 of any message exceeds the number specified.
4225
4226 @item -n
4227 @itemx --nullterminate
4228 Terminate message text in @code{bin} files by zero. By default they are
4229 terminated by CR/LF.
4230
4231 @item -o
4232 @itemx --hresult_use
4233 Not yet implemented. Instructs @code{windmc} to generate an OLE2 header
4234 file, using HRESULT definitions. Status codes are used if the flag is not
4235 specified.
4236
4237 @item -O @var{codepage}
4238 @itemx --codepage_out @var{codepage}
4239 Sets the default codepage to be used to output text files. The default
4240 is ocdepage 1252.
4241
4242 @item -r @var{path}
4243 @itemx --rcdir @var{path}
4244 The target directory for the generated @code{rc} script and the generated
4245 @code{bin} files that the resource compiler script includes. The default
4246 is the current directory.
4247
4248 @item -u
4249 @itemx --unicode_in
4250 Specifies that the input file is UTF16.
4251
4252 @item -U
4253 @itemx --unicode_out
4254 Specifies that messages in the output @code{bin} file should be in UTF16
4255 format. This is the default behaviour.
4256
4257 @item -v
4258 @item --verbose
4259 Enable verbose mode.
4260
4261 @item -V
4262 @item --version
4263 Prints the version number for @command{windmc}.
4264
4265 @item -x @var{path}
4266 @itemx --xdgb @var{path}
4267 The path of the @code{dbg} C include file that maps message id's to the
4268 symbolic name. No such file is generated without specifying the switch.
4269 @end table
4270
4271 @c man end
4272
4273 @ignore
4274 @c man begin SEEALSO windmc
4275 the Info entries for @file{binutils}.
4276 @c man end
4277 @end ignore
4278
4279 @node windres
4280 @chapter windres
4281
4282 @command{windres} may be used to manipulate Windows resources.
4283
4284 @quotation
4285 @emph{Warning:} @command{windres} is not always built as part of the binary
4286 utilities, since it is only useful for Windows targets.
4287 @end quotation
4288
4289 @c man title windres manipulate Windows resources
4290
4291 @smallexample
4292 @c man begin SYNOPSIS windres
4293 windres [options] [input-file] [output-file]
4294 @c man end
4295 @end smallexample
4296
4297 @c man begin DESCRIPTION windres
4298
4299 @command{windres} reads resources from an input file and copies them into
4300 an output file. Either file may be in one of three formats:
4301
4302 @table @code
4303 @item rc
4304 A text format read by the Resource Compiler.
4305
4306 @item res
4307 A binary format generated by the Resource Compiler.
4308
4309 @item coff
4310 A COFF object or executable.
4311 @end table
4312
4313 The exact description of these different formats is available in
4314 documentation from Microsoft.
4315
4316 When @command{windres} converts from the @code{rc} format to the @code{res}
4317 format, it is acting like the Windows Resource Compiler. When
4318 @command{windres} converts from the @code{res} format to the @code{coff}
4319 format, it is acting like the Windows @code{CVTRES} program.
4320
4321 When @command{windres} generates an @code{rc} file, the output is similar
4322 but not identical to the format expected for the input. When an input
4323 @code{rc} file refers to an external filename, an output @code{rc} file
4324 will instead include the file contents.
4325
4326 If the input or output format is not specified, @command{windres} will
4327 guess based on the file name, or, for the input file, the file contents.
4328 A file with an extension of @file{.rc} will be treated as an @code{rc}
4329 file, a file with an extension of @file{.res} will be treated as a
4330 @code{res} file, and a file with an extension of @file{.o} or
4331 @file{.exe} will be treated as a @code{coff} file.
4332
4333 If no output file is specified, @command{windres} will print the resources
4334 in @code{rc} format to standard output.
4335
4336 The normal use is for you to write an @code{rc} file, use @command{windres}
4337 to convert it to a COFF object file, and then link the COFF file into
4338 your application. This will make the resources described in the
4339 @code{rc} file available to Windows.
4340
4341 @c man end
4342
4343 @c man begin OPTIONS windres
4344
4345 @table @env
4346 @item -i @var{filename}
4347 @itemx --input @var{filename}
4348 The name of the input file. If this option is not used, then
4349 @command{windres} will use the first non-option argument as the input file
4350 name. If there are no non-option arguments, then @command{windres} will
4351 read from standard input. @command{windres} can not read a COFF file from
4352 standard input.
4353
4354 @item -o @var{filename}
4355 @itemx --output @var{filename}
4356 The name of the output file. If this option is not used, then
4357 @command{windres} will use the first non-option argument, after any used
4358 for the input file name, as the output file name. If there is no
4359 non-option argument, then @command{windres} will write to standard output.
4360 @command{windres} can not write a COFF file to standard output. Note,
4361 for compatibility with @command{rc} the option @option{-fo} is also
4362 accepted, but its use is not recommended.
4363
4364 @item -J @var{format}
4365 @itemx --input-format @var{format}
4366 The input format to read. @var{format} may be @samp{res}, @samp{rc}, or
4367 @samp{coff}. If no input format is specified, @command{windres} will
4368 guess, as described above.
4369
4370 @item -O @var{format}
4371 @itemx --output-format @var{format}
4372 The output format to generate. @var{format} may be @samp{res},
4373 @samp{rc}, or @samp{coff}. If no output format is specified,
4374 @command{windres} will guess, as described above.
4375
4376 @item -F @var{target}
4377 @itemx --target @var{target}
4378 Specify the BFD format to use for a COFF file as input or output. This
4379 is a BFD target name; you can use the @option{--help} option to see a list
4380 of supported targets. Normally @command{windres} will use the default
4381 format, which is the first one listed by the @option{--help} option.
4382 @ifclear man
4383 @ref{Target Selection}.
4384 @end ifclear
4385
4386 @item --preprocessor @var{program}
4387 When @command{windres} reads an @code{rc} file, it runs it through the C
4388 preprocessor first. This option may be used to specify the preprocessor
4389 to use. The default preprocessor is @code{gcc}.
4390
4391 @item --preprocessor-arg @var{option}
4392 When @command{windres} reads an @code{rc} file, it runs it through
4393 the C preprocessor first. This option may be used to specify additional
4394 text to be passed to preprocessor on its command line.
4395 This option can be used multiple times to add multiple options to the
4396 preprocessor command line.
4397 If the @option{--preprocessor} option has not been specified then a
4398 default set of preprocessor arguments will be used, with any
4399 @option{--preprocessor-arg} options being placed after them on the
4400 command line. These default arguments are @code{-E},
4401 @code{-xc-header} and @code{-DRC_INVOKED}.
4402
4403 @item -I @var{directory}
4404 @itemx --include-dir @var{directory}
4405 Specify an include directory to use when reading an @code{rc} file.
4406 @command{windres} will pass this to the preprocessor as an @option{-I}
4407 option. @command{windres} will also search this directory when looking for
4408 files named in the @code{rc} file. If the argument passed to this command
4409 matches any of the supported @var{formats} (as described in the @option{-J}
4410 option), it will issue a deprecation warning, and behave just like the
4411 @option{-J} option. New programs should not use this behaviour. If a
4412 directory happens to match a @var{format}, simple prefix it with @samp{./}
4413 to disable the backward compatibility.
4414
4415 @item -D @var{target}
4416 @itemx --define @var{sym}[=@var{val}]
4417 Specify a @option{-D} option to pass to the preprocessor when reading an
4418 @code{rc} file.
4419
4420 @item -U @var{target}
4421 @itemx --undefine @var{sym}
4422 Specify a @option{-U} option to pass to the preprocessor when reading an
4423 @code{rc} file.
4424
4425 @item -r
4426 Ignored for compatibility with rc.
4427
4428 @item -v
4429 Enable verbose mode. This tells you what the preprocessor is if you
4430 didn't specify one.
4431
4432 @item -c @var{val}
4433 @item --codepage @var{val}
4434 Specify the default codepage to use when reading an @code{rc} file.
4435 @var{val} should be a hexadecimal prefixed by @samp{0x} or decimal
4436 codepage code. The valid range is from zero up to 0xffff, but the
4437 validity of the codepage is host and configuration dependent.
4438
4439 @item -l @var{val}
4440 @item --language @var{val}
4441 Specify the default language to use when reading an @code{rc} file.
4442 @var{val} should be a hexadecimal language code. The low eight bits are
4443 the language, and the high eight bits are the sublanguage.
4444
4445 @item --use-temp-file
4446 Use a temporary file to instead of using popen to read the output of
4447 the preprocessor. Use this option if the popen implementation is buggy
4448 on the host (eg., certain non-English language versions of Windows 95 and
4449 Windows 98 are known to have buggy popen where the output will instead
4450 go the console).
4451
4452 @item --no-use-temp-file
4453 Use popen, not a temporary file, to read the output of the preprocessor.
4454 This is the default behaviour.
4455
4456 @item -h
4457 @item --help
4458 Prints a usage summary.
4459
4460 @item -V
4461 @item --version
4462 Prints the version number for @command{windres}.
4463
4464 @item --yydebug
4465 If @command{windres} is compiled with @code{YYDEBUG} defined as @code{1},
4466 this will turn on parser debugging.
4467 @end table
4468
4469 @c man end
4470
4471 @ignore
4472 @c man begin SEEALSO windres
4473 the Info entries for @file{binutils}.
4474 @c man end
4475 @end ignore
4476
4477 @node dlltool
4478 @chapter dlltool
4479 @cindex DLL
4480 @kindex dlltool
4481
4482 @command{dlltool} is used to create the files needed to create dynamic
4483 link libraries (DLLs) on systems which understand PE format image
4484 files such as Windows. A DLL contains an export table which contains
4485 information that the runtime loader needs to resolve references from a
4486 referencing program.
4487
4488 The export table is generated by this program by reading in a
4489 @file{.def} file or scanning the @file{.a} and @file{.o} files which
4490 will be in the DLL. A @file{.o} file can contain information in
4491 special @samp{.drectve} sections with export information.
4492
4493 @quotation
4494 @emph{Note:} @command{dlltool} is not always built as part of the
4495 binary utilities, since it is only useful for those targets which
4496 support DLLs.
4497 @end quotation
4498
4499 @c man title dlltool create files needed to build and use DLLs
4500
4501 @smallexample
4502 @c man begin SYNOPSIS dlltool
4503 dlltool [@option{-d}|@option{--input-def} @var{def-file-name}]
4504 [@option{-b}|@option{--base-file} @var{base-file-name}]
4505 [@option{-e}|@option{--output-exp} @var{exports-file-name}]
4506 [@option{-z}|@option{--output-def} @var{def-file-name}]
4507 [@option{-l}|@option{--output-lib} @var{library-file-name}]
4508 [@option{-y}|@option{--output-delaylib} @var{library-file-name}]
4509 [@option{--export-all-symbols}] [@option{--no-export-all-symbols}]
4510 [@option{--exclude-symbols} @var{list}]
4511 [@option{--no-default-excludes}]
4512 [@option{-S}|@option{--as} @var{path-to-assembler}] [@option{-f}|@option{--as-flags} @var{options}]
4513 [@option{-D}|@option{--dllname} @var{name}] [@option{-m}|@option{--machine} @var{machine}]
4514 [@option{-a}|@option{--add-indirect}]
4515 [@option{-U}|@option{--add-underscore}] [@option{--add-stdcall-underscore}]
4516 [@option{-k}|@option{--kill-at}] [@option{-A}|@option{--add-stdcall-alias}]
4517 [@option{-p}|@option{--ext-prefix-alias} @var{prefix}]
4518 [@option{-x}|@option{--no-idata4}] [@option{-c}|@option{--no-idata5}]
4519 [@option{--use-nul-prefixed-import-tables}]
4520 [@option{-I}|@option{--identify} @var{library-file-name}] [@option{--identify-strict}]
4521 [@option{-i}|@option{--interwork}]
4522 [@option{-n}|@option{--nodelete}] [@option{-t}|@option{--temp-prefix} @var{prefix}]
4523 [@option{-v}|@option{--verbose}]
4524 [@option{-h}|@option{--help}] [@option{-V}|@option{--version}]
4525 [@option{--no-leading-underscore}] [@option{--leading-underscore}]
4526 [@option{--deterministic-libraries}] [@option{--non-deterministic-libraries}]
4527 [object-file @dots{}]
4528 @c man end
4529 @end smallexample
4530
4531 @c man begin DESCRIPTION dlltool
4532
4533 @command{dlltool} reads its inputs, which can come from the @option{-d} and
4534 @option{-b} options as well as object files specified on the command
4535 line. It then processes these inputs and if the @option{-e} option has
4536 been specified it creates a exports file. If the @option{-l} option
4537 has been specified it creates a library file and if the @option{-z} option
4538 has been specified it creates a def file. Any or all of the @option{-e},
4539 @option{-l} and @option{-z} options can be present in one invocation of
4540 dlltool.
4541
4542 When creating a DLL, along with the source for the DLL, it is necessary
4543 to have three other files. @command{dlltool} can help with the creation of
4544 these files.
4545
4546 The first file is a @file{.def} file which specifies which functions are
4547 exported from the DLL, which functions the DLL imports, and so on. This
4548 is a text file and can be created by hand, or @command{dlltool} can be used
4549 to create it using the @option{-z} option. In this case @command{dlltool}
4550 will scan the object files specified on its command line looking for
4551 those functions which have been specially marked as being exported and
4552 put entries for them in the @file{.def} file it creates.
4553
4554 In order to mark a function as being exported from a DLL, it needs to
4555 have an @option{-export:<name_of_function>} entry in the @samp{.drectve}
4556 section of the object file. This can be done in C by using the
4557 asm() operator:
4558
4559 @smallexample
4560 asm (".section .drectve");
4561 asm (".ascii \"-export:my_func\"");
4562
4563 int my_func (void) @{ @dots{} @}
4564 @end smallexample
4565
4566 The second file needed for DLL creation is an exports file. This file
4567 is linked with the object files that make up the body of the DLL and it
4568 handles the interface between the DLL and the outside world. This is a
4569 binary file and it can be created by giving the @option{-e} option to
4570 @command{dlltool} when it is creating or reading in a @file{.def} file.
4571
4572 The third file needed for DLL creation is the library file that programs
4573 will link with in order to access the functions in the DLL (an `import
4574 library'). This file can be created by giving the @option{-l} option to
4575 dlltool when it is creating or reading in a @file{.def} file.
4576
4577 If the @option{-y} option is specified, dlltool generates a delay-import
4578 library that can be used instead of the normal import library to allow
4579 a program to link to the dll only as soon as an imported function is
4580 called for the first time. The resulting executable will need to be
4581 linked to the static delayimp library containing __delayLoadHelper2(),
4582 which in turn will import LoadLibraryA and GetProcAddress from kernel32.
4583
4584 @command{dlltool} builds the library file by hand, but it builds the
4585 exports file by creating temporary files containing assembler statements
4586 and then assembling these. The @option{-S} command-line option can be
4587 used to specify the path to the assembler that dlltool will use,
4588 and the @option{-f} option can be used to pass specific flags to that
4589 assembler. The @option{-n} can be used to prevent dlltool from deleting
4590 these temporary assembler files when it is done, and if @option{-n} is
4591 specified twice then this will prevent dlltool from deleting the
4592 temporary object files it used to build the library.
4593
4594 Here is an example of creating a DLL from a source file @samp{dll.c} and
4595 also creating a program (from an object file called @samp{program.o})
4596 that uses that DLL:
4597
4598 @smallexample
4599 gcc -c dll.c
4600 dlltool -e exports.o -l dll.lib dll.o
4601 gcc dll.o exports.o -o dll.dll
4602 gcc program.o dll.lib -o program
4603 @end smallexample
4604
4605
4606 @command{dlltool} may also be used to query an existing import library
4607 to determine the name of the DLL to which it is associated. See the
4608 description of the @option{-I} or @option{--identify} option.
4609
4610 @c man end
4611
4612 @c man begin OPTIONS dlltool
4613
4614 The command-line options have the following meanings:
4615
4616 @table @env
4617
4618 @item -d @var{filename}
4619 @itemx --input-def @var{filename}
4620 @cindex input .def file
4621 Specifies the name of a @file{.def} file to be read in and processed.
4622
4623 @item -b @var{filename}
4624 @itemx --base-file @var{filename}
4625 @cindex base files
4626 Specifies the name of a base file to be read in and processed. The
4627 contents of this file will be added to the relocation section in the
4628 exports file generated by dlltool.
4629
4630 @item -e @var{filename}
4631 @itemx --output-exp @var{filename}
4632 Specifies the name of the export file to be created by dlltool.
4633
4634 @item -z @var{filename}
4635 @itemx --output-def @var{filename}
4636 Specifies the name of the @file{.def} file to be created by dlltool.
4637
4638 @item -l @var{filename}
4639 @itemx --output-lib @var{filename}
4640 Specifies the name of the library file to be created by dlltool.
4641
4642 @item -y @var{filename}
4643 @itemx --output-delaylib @var{filename}
4644 Specifies the name of the delay-import library file to be created by dlltool.
4645
4646 @item --deterministic-libraries
4647 @itemx --non-deterministic-libraries
4648 When creating output libraries in response to either the
4649 @option{--output-lib} or @option{--output-delaylib} options either use
4650 the value of zero for any timestamps, user ids and group ids created
4651 (@option{--deterministic-libraries}) or the actual timestamps, user
4652 ids and group ids (@option{--non-deterministic-libraries}).
4653
4654 @item --export-all-symbols
4655 Treat all global and weak defined symbols found in the input object
4656 files as symbols to be exported. There is a small list of symbols which
4657 are not exported by default; see the @option{--no-default-excludes}
4658 option. You may add to the list of symbols to not export by using the
4659 @option{--exclude-symbols} option.
4660
4661 @item --no-export-all-symbols
4662 Only export symbols explicitly listed in an input @file{.def} file or in
4663 @samp{.drectve} sections in the input object files. This is the default
4664 behaviour. The @samp{.drectve} sections are created by @samp{dllexport}
4665 attributes in the source code.
4666
4667 @item --exclude-symbols @var{list}
4668 Do not export the symbols in @var{list}. This is a list of symbol names
4669 separated by comma or colon characters. The symbol names should not
4670 contain a leading underscore. This is only meaningful when
4671 @option{--export-all-symbols} is used.
4672
4673 @item --no-default-excludes
4674 When @option{--export-all-symbols} is used, it will by default avoid
4675 exporting certain special symbols. The current list of symbols to avoid
4676 exporting is @samp{DllMain@@12}, @samp{DllEntryPoint@@0},
4677 @samp{impure_ptr}. You may use the @option{--no-default-excludes} option
4678 to go ahead and export these special symbols. This is only meaningful
4679 when @option{--export-all-symbols} is used.
4680
4681 @item -S @var{path}
4682 @itemx --as @var{path}
4683 Specifies the path, including the filename, of the assembler to be used
4684 to create the exports file.
4685
4686 @item -f @var{options}
4687 @itemx --as-flags @var{options}
4688 Specifies any specific command-line options to be passed to the
4689 assembler when building the exports file. This option will work even if
4690 the @option{-S} option is not used. This option only takes one argument,
4691 and if it occurs more than once on the command line, then later
4692 occurrences will override earlier occurrences. So if it is necessary to
4693 pass multiple options to the assembler they should be enclosed in
4694 double quotes.
4695
4696 @item -D @var{name}
4697 @itemx --dll-name @var{name}
4698 Specifies the name to be stored in the @file{.def} file as the name of
4699 the DLL when the @option{-e} option is used. If this option is not
4700 present, then the filename given to the @option{-e} option will be
4701 used as the name of the DLL.
4702
4703 @item -m @var{machine}
4704 @itemx -machine @var{machine}
4705 Specifies the type of machine for which the library file should be
4706 built. @command{dlltool} has a built in default type, depending upon how
4707 it was created, but this option can be used to override that. This is
4708 normally only useful when creating DLLs for an ARM processor, when the
4709 contents of the DLL are actually encode using Thumb instructions.
4710
4711 @item -a
4712 @itemx --add-indirect
4713 Specifies that when @command{dlltool} is creating the exports file it
4714 should add a section which allows the exported functions to be
4715 referenced without using the import library. Whatever the hell that
4716 means!
4717
4718 @item -U
4719 @itemx --add-underscore
4720 Specifies that when @command{dlltool} is creating the exports file it
4721 should prepend an underscore to the names of @emph{all} exported symbols.
4722
4723 @item --no-leading-underscore
4724 @item --leading-underscore
4725 Specifies whether standard symbol should be forced to be prefixed, or
4726 not.
4727
4728 @item --add-stdcall-underscore
4729 Specifies that when @command{dlltool} is creating the exports file it
4730 should prepend an underscore to the names of exported @emph{stdcall}
4731 functions. Variable names and non-stdcall function names are not modified.
4732 This option is useful when creating GNU-compatible import libs for third
4733 party DLLs that were built with MS-Windows tools.
4734
4735 @item -k
4736 @itemx --kill-at
4737 Specifies that @samp{@@<number>} suffixes should be omitted from the names
4738 of stdcall functions that will be imported from the DLL. This is
4739 useful when creating an import library for a DLL which exports stdcall
4740 functions but without the usual @samp{@@<number>} symbol name suffix.
4741
4742 This does not change the naming of symbols provided by the import library
4743 to programs linked against it, but only the entries in the import table
4744 (ie the .idata section).
4745
4746 @item -A
4747 @itemx --add-stdcall-alias
4748 Specifies that when @command{dlltool} is creating the exports file it
4749 should add aliases for stdcall symbols without @samp{@@ <number>}
4750 in addition to the symbols with @samp{@@ <number>}.
4751
4752 @item -p
4753 @itemx --ext-prefix-alias @var{prefix}
4754 Causes @command{dlltool} to create external aliases for all DLL
4755 imports with the specified prefix. The aliases are created for both
4756 external and import symbols with no leading underscore.
4757
4758 @item -x
4759 @itemx --no-idata4
4760 Specifies that when @command{dlltool} is creating the exports and library
4761 files it should omit the @code{.idata4} section. This is for compatibility
4762 with certain operating systems.
4763
4764 @item --use-nul-prefixed-import-tables
4765 Specifies that when @command{dlltool} is creating the exports and library
4766 files it should prefix the @code{.idata4} and @code{.idata5} by zero an
4767 element. This emulates old gnu import library generation of
4768 @code{dlltool}. By default this option is turned off.
4769
4770 @item -c
4771 @itemx --no-idata5
4772 Specifies that when @command{dlltool} is creating the exports and library
4773 files it should omit the @code{.idata5} section. This is for compatibility
4774 with certain operating systems.
4775
4776 @item -I @var{filename}
4777 @itemx --identify @var{filename}
4778 Specifies that @command{dlltool} should inspect the import library
4779 indicated by @var{filename} and report, on @code{stdout}, the name(s)
4780 of the associated DLL(s). This can be performed in addition to any
4781 other operations indicated by the other options and arguments.
4782 @command{dlltool} fails if the import library does not exist or is not
4783 actually an import library. See also @option{--identify-strict}.
4784
4785 @item --identify-strict
4786 Modifies the behavior of the @option{--identify} option, such
4787 that an error is reported if @var{filename} is associated with
4788 more than one DLL.
4789
4790 @item -i
4791 @itemx --interwork
4792 Specifies that @command{dlltool} should mark the objects in the library
4793 file and exports file that it produces as supporting interworking
4794 between ARM and Thumb code.
4795
4796 @item -n
4797 @itemx --nodelete
4798 Makes @command{dlltool} preserve the temporary assembler files it used to
4799 create the exports file. If this option is repeated then dlltool will
4800 also preserve the temporary object files it uses to create the library
4801 file.
4802
4803 @item -t @var{prefix}
4804 @itemx --temp-prefix @var{prefix}
4805 Makes @command{dlltool} use @var{prefix} when constructing the names of
4806 temporary assembler and object files. By default, the temp file prefix
4807 is generated from the pid.
4808
4809 @item -v
4810 @itemx --verbose
4811 Make dlltool describe what it is doing.
4812
4813 @item -h
4814 @itemx --help
4815 Displays a list of command-line options and then exits.
4816
4817 @item -V
4818 @itemx --version
4819 Displays dlltool's version number and then exits.
4820
4821 @end table
4822
4823 @c man end
4824
4825 @menu
4826 * def file format:: The format of the dlltool @file{.def} file
4827 @end menu
4828
4829 @node def file format
4830 @section The format of the @command{dlltool} @file{.def} file
4831
4832 A @file{.def} file contains any number of the following commands:
4833
4834 @table @asis
4835
4836 @item @code{NAME} @var{name} @code{[ ,} @var{base} @code{]}
4837 The result is going to be named @var{name}@code{.exe}.
4838
4839 @item @code{LIBRARY} @var{name} @code{[ ,} @var{base} @code{]}
4840 The result is going to be named @var{name}@code{.dll}.
4841 Note: If you want to use LIBRARY as name then you need to quote. Otherwise
4842 this will fail due a necessary hack for libtool (see PR binutils/13710 for more
4843 details).
4844
4845 @item @code{EXPORTS ( ( (} @var{name1} @code{[ = } @var{name2} @code{] ) | ( } @var{name1} @code{=} @var{module-name} @code{.} @var{external-name} @code{) ) [ == } @var{its_name} @code{]}
4846 @item @code{[} @var{integer} @code{] [ NONAME ] [ CONSTANT ] [ DATA ] [ PRIVATE ] ) *}
4847 Declares @var{name1} as an exported symbol from the DLL, with optional
4848 ordinal number @var{integer}, or declares @var{name1} as an alias
4849 (forward) of the function @var{external-name} in the DLL.
4850 If @var{its_name} is specified, this name is used as string in export table.
4851 @var{module-name}.
4852 Note: The @code{EXPORTS} has to be the last command in .def file, as keywords
4853 are treated - beside @code{LIBRARY} - as simple name-identifiers.
4854 If you want to use LIBRARY as name then you need to quote it.
4855
4856 @item @code{IMPORTS ( (} @var{internal-name} @code{=} @var{module-name} @code{.} @var{integer} @code{) | [} @var{internal-name} @code{= ]} @var{module-name} @code{.} @var{external-name} @code{) [ == ) @var{its_name} @code{]} *}
4857 Declares that @var{external-name} or the exported function whose
4858 ordinal number is @var{integer} is to be imported from the file
4859 @var{module-name}. If @var{internal-name} is specified then this is
4860 the name that the imported function will be referred to in the body of
4861 the DLL.
4862 If @var{its_name} is specified, this name is used as string in import table.
4863 Note: The @code{IMPORTS} has to be the last command in .def file, as keywords
4864 are treated - beside @code{LIBRARY} - as simple name-identifiers.
4865 If you want to use LIBRARY as name then you need to quote it.
4866
4867 @item @code{DESCRIPTION} @var{string}
4868 Puts @var{string} into the output @file{.exp} file in the
4869 @code{.rdata} section.
4870
4871 @item @code{STACKSIZE} @var{number-reserve} @code{[, } @var{number-commit} @code{]}
4872 @item @code{HEAPSIZE} @var{number-reserve} @code{[, } @var{number-commit} @code{]}
4873 Generates @code{--stack} or @code{--heap}
4874 @var{number-reserve},@var{number-commit} in the output @code{.drectve}
4875 section. The linker will see this and act upon it.
4876
4877 @item @code{CODE} @var{attr} @code{+}
4878 @item @code{DATA} @var{attr} @code{+}
4879 @item @code{SECTIONS (} @var{section-name} @var{attr}@code{ + ) *}
4880 Generates @code{--attr} @var{section-name} @var{attr} in the output
4881 @code{.drectve} section, where @var{attr} is one of @code{READ},
4882 @code{WRITE}, @code{EXECUTE} or @code{SHARED}. The linker will see
4883 this and act upon it.
4884
4885 @end table
4886
4887 @ignore
4888 @c man begin SEEALSO dlltool
4889 The Info pages for @file{binutils}.
4890 @c man end
4891 @end ignore
4892
4893 @node readelf
4894 @chapter readelf
4895
4896 @cindex ELF file information
4897 @kindex readelf
4898
4899 @c man title readelf display information about ELF files
4900
4901 @smallexample
4902 @c man begin SYNOPSIS readelf
4903 readelf [@option{-a}|@option{--all}]
4904 [@option{-h}|@option{--file-header}]
4905 [@option{-l}|@option{--program-headers}|@option{--segments}]
4906 [@option{-S}|@option{--section-headers}|@option{--sections}]
4907 [@option{-g}|@option{--section-groups}]
4908 [@option{-t}|@option{--section-details}]
4909 [@option{-e}|@option{--headers}]
4910 [@option{-s}|@option{--syms}|@option{--symbols}]
4911 [@option{--dyn-syms}|@option{--lto-syms}]
4912 [@option{--sym-base=[0|8|10|16]}]
4913 [@option{--demangle@var{=style}}|@option{--no-demangle}]
4914 [@option{--quiet}]
4915 [@option{--recurse-limit}|@option{--no-recurse-limit}]
4916 [@option{-U} @var{method}|@option{--unicode=}@var{method}]
4917 [@option{-n}|@option{--notes}]
4918 [@option{-r}|@option{--relocs}]
4919 [@option{-u}|@option{--unwind}]
4920 [@option{-d}|@option{--dynamic}]
4921 [@option{-V}|@option{--version-info}]
4922 [@option{-A}|@option{--arch-specific}]
4923 [@option{-D}|@option{--use-dynamic}]
4924 [@option{-L}|@option{--lint}|@option{--enable-checks}]
4925 [@option{-x} <number or name>|@option{--hex-dump=}<number or name>]
4926 [@option{-p} <number or name>|@option{--string-dump=}<number or name>]
4927 [@option{-R} <number or name>|@option{--relocated-dump=}<number or name>]
4928 [@option{-z}|@option{--decompress}]
4929 [@option{-c}|@option{--archive-index}]
4930 [@option{-w[lLiaprmfFsoORtUuTgAck]}|
4931 @option{--debug-dump}[=rawline,=decodedline,=info,=abbrev,=pubnames,=aranges,=macro,=frames,=frames-interp,=str,=str-offsets,=loc,=Ranges,=pubtypes,=trace_info,=trace_abbrev,=trace_aranges,=gdb_index,=addr,=cu_index,=links]]
4932 [@option{-wK}|@option{--debug-dump=follow-links}]
4933 [@option{-wN}|@option{--debug-dump=no-follow-links}]
4934 [@option{-wD}|@option{--debug-dump=use-debuginfod}]
4935 [@option{-wE}|@option{--debug-dump=do-not-use-debuginfod}]
4936 [@option{-P}|@option{--process-links}]
4937 [@option{--dwarf-depth=@var{n}}]
4938 [@option{--dwarf-start=@var{n}}]
4939 [@option{--ctf=}@var{section}]
4940 [@option{--ctf-parent=}@var{section}]
4941 [@option{--ctf-symbols=}@var{section}]
4942 [@option{--ctf-strings=}@var{section}]
4943 [@option{-I}|@option{--histogram}]
4944 [@option{-v}|@option{--version}]
4945 [@option{-W}|@option{--wide}]
4946 [@option{-T}|@option{--silent-truncation}]
4947 [@option{-H}|@option{--help}]
4948 @var{elffile}@dots{}
4949 @c man end
4950 @end smallexample
4951
4952 @c man begin DESCRIPTION readelf
4953
4954 @command{readelf} displays information about one or more ELF format object
4955 files. The options control what particular information to display.
4956
4957 @var{elffile}@dots{} are the object files to be examined. 32-bit and
4958 64-bit ELF files are supported, as are archives containing ELF files.
4959
4960 This program performs a similar function to @command{objdump} but it
4961 goes into more detail and it exists independently of the @sc{bfd}
4962 library, so if there is a bug in @sc{bfd} then readelf will not be
4963 affected.
4964
4965 @c man end
4966
4967 @c man begin OPTIONS readelf
4968
4969 The long and short forms of options, shown here as alternatives, are
4970 equivalent. At least one option besides @samp{-v} or @samp{-H} must be
4971 given.
4972
4973 @table @env
4974 @item -a
4975 @itemx --all
4976 Equivalent to specifying @option{--file-header},
4977 @option{--program-headers}, @option{--sections}, @option{--symbols},
4978 @option{--relocs}, @option{--dynamic}, @option{--notes},
4979 @option{--version-info}, @option{--arch-specific}, @option{--unwind},
4980 @option{--section-groups} and @option{--histogram}.
4981
4982 Note - this option does not enable @option{--use-dynamic} itself, so
4983 if that option is not present on the command line then dynamic symbols
4984 and dynamic relocs will not be displayed.
4985
4986 @item -h
4987 @itemx --file-header
4988 @cindex ELF file header information
4989 Displays the information contained in the ELF header at the start of the
4990 file.
4991
4992 @item -l
4993 @itemx --program-headers
4994 @itemx --segments
4995 @cindex ELF program header information
4996 @cindex ELF segment information
4997 Displays the information contained in the file's segment headers, if it
4998 has any.
4999
5000 @item --quiet
5001 @cindex quiet
5002 Suppress "no symbols" diagnostic.
5003
5004 @item -S
5005 @itemx --sections
5006 @itemx --section-headers
5007 @cindex ELF section information
5008 Displays the information contained in the file's section headers, if it
5009 has any.
5010
5011 @item -g
5012 @itemx --section-groups
5013 @cindex ELF section group information
5014 Displays the information contained in the file's section groups, if it
5015 has any.
5016
5017 @item -t
5018 @itemx --section-details
5019 @cindex ELF section information
5020 Displays the detailed section information. Implies @option{-S}.
5021
5022 @item -s
5023 @itemx --symbols
5024 @itemx --syms
5025 @cindex ELF symbol table information
5026 Displays the entries in symbol table section of the file, if it has one.
5027 If a symbol has version information associated with it then this is
5028 displayed as well. The version string is displayed as a suffix to the
5029 symbol name, preceded by an @@ character. For example
5030 @samp{foo@@VER_1}. If the version is the default version to be used
5031 when resolving unversioned references to the symbol then it is
5032 displayed as a suffix preceded by two @@ characters. For example
5033 @samp{foo@@@@VER_2}.
5034
5035 @item --dyn-syms
5036 @cindex ELF dynamic symbol table information
5037 Displays the entries in dynamic symbol table section of the file, if it
5038 has one. The output format is the same as the format used by the
5039 @option{--syms} option.
5040
5041 @item --lto-syms
5042 @cindex LTO symbol table
5043 Displays the contents of any LTO symbol tables in the file.
5044
5045 @item --sym-base=[0|8|10|16]
5046 @cindex symbol table size base
5047 Forces the size field of the symbol table to use the given base. Any
5048 unrecognized options will be treated as @samp{0}. @option{--sym-base=0}
5049 represents the default and legacy behaviour. This will output sizes as decimal
5050 for numbers less than 100000. For sizes 100000 and greater hexadecimal notation
5051 will be used with a 0x prefix.
5052 @option{--sym-base=8} will give the symbol sizes in octal.
5053 @option{--sym-base=10} will always give the symbol sizes in decimal.
5054 @option{--sym-base=16} will always give the symbol sizes in hexadecimal with a
5055 0x prefix.
5056
5057 @item -C
5058 @itemx --demangle[=@var{style}]
5059 @cindex demangling in nm
5060 Decode (@dfn{demangle}) low-level symbol names into user-level names.
5061 This makes C++ function names readable. Different compilers have
5062 different mangling styles. The optional demangling style argument can
5063 be used to choose an appropriate demangling style for your
5064 compiler. @xref{c++filt}, for more information on demangling.
5065
5066 @item --no-demangle
5067 Do not demangle low-level symbol names. This is the default.
5068
5069 @item --recurse-limit
5070 @itemx --no-recurse-limit
5071 @itemx --recursion-limit
5072 @itemx --no-recursion-limit
5073 Enables or disables a limit on the amount of recursion performed
5074 whilst demangling strings. Since the name mangling formats allow for
5075 an infinite level of recursion it is possible to create strings whose
5076 decoding will exhaust the amount of stack space available on the host
5077 machine, triggering a memory fault. The limit tries to prevent this
5078 from happening by restricting recursion to 2048 levels of nesting.
5079
5080 The default is for this limit to be enabled, but disabling it may be
5081 necessary in order to demangle truly complicated names. Note however
5082 that if the recursion limit is disabled then stack exhaustion is
5083 possible and any bug reports about such an event will be rejected.
5084
5085 @item -U @var{[d|i|l|e|x|h]}
5086 @itemx --unicode=[default|invalid|locale|escape|hex|highlight]
5087 Controls the display of non-ASCII characters in identifier names.
5088 The default (@option{--unicode=locale} or @option{--unicode=default}) is
5089 to treat them as multibyte characters and display them in the current
5090 locale. All other versions of this option treat the bytes as UTF-8
5091 encoded values and attempt to interpret them. If they cannot be
5092 interpreted or if the @option{--unicode=invalid} option is used then
5093 they are displayed as a sequence of hex bytes, encloses in curly
5094 parethesis characters.
5095
5096 Using the @option{--unicode=escape} option will display the characters
5097 as as unicode escape sequences (@var{\uxxxx}). Using the
5098 @option{--unicode=hex} will display the characters as hex byte
5099 sequences enclosed between angle brackets.
5100
5101 Using the @option{--unicode=highlight} will display the characters as
5102 unicode escape sequences but it will also highlighted them in red,
5103 assuming that colouring is supported by the output device. The
5104 colouring is intended to draw attention to the presence of unicode
5105 sequences when they might not be expected.
5106
5107 @item -e
5108 @itemx --headers
5109 Display all the headers in the file. Equivalent to @option{-h -l -S}.
5110
5111 @item -n
5112 @itemx --notes
5113 @cindex ELF notes
5114 Displays the contents of the NOTE segments and/or sections, if any.
5115
5116 @item -r
5117 @itemx --relocs
5118 @cindex ELF reloc information
5119 Displays the contents of the file's relocation section, if it has one.
5120
5121 @item -u
5122 @itemx --unwind
5123 @cindex unwind information
5124 Displays the contents of the file's unwind section, if it has one. Only
5125 the unwind sections for IA64 ELF files, as well as ARM unwind tables
5126 (@code{.ARM.exidx} / @code{.ARM.extab}) are currently supported. If
5127 support is not yet implemented for your architecture you could try
5128 dumping the contents of the @var{.eh_frames} section using the
5129 @option{--debug-dump=frames} or @option{--debug-dump=frames-interp}
5130 options.
5131
5132 @item -d
5133 @itemx --dynamic
5134 @cindex ELF dynamic section information
5135 Displays the contents of the file's dynamic section, if it has one.
5136
5137 @item -V
5138 @itemx --version-info
5139 @cindex ELF version sections information
5140 Displays the contents of the version sections in the file, it they
5141 exist.
5142
5143 @item -A
5144 @itemx --arch-specific
5145 Displays architecture-specific information in the file, if there
5146 is any.
5147
5148 @item -D
5149 @itemx --use-dynamic
5150 When displaying symbols, this option makes @command{readelf} use the
5151 symbol hash tables in the file's dynamic section, rather than the
5152 symbol table sections.
5153
5154 When displaying relocations, this option makes @command{readelf}
5155 display the dynamic relocations rather than the static relocations.
5156
5157 @item -L
5158 @itemx --lint
5159 @itemx --enable-checks
5160 Displays warning messages about possible problems with the file(s)
5161 being examined. If used on its own then all of the contents of the
5162 file(s) will be examined. If used with one of the dumping options
5163 then the warning messages will only be produced for the things being
5164 displayed.
5165
5166 @item -x <number or name>
5167 @itemx --hex-dump=<number or name>
5168 Displays the contents of the indicated section as a hexadecimal bytes.
5169 A number identifies a particular section by index in the section table;
5170 any other string identifies all sections with that name in the object file.
5171
5172 @item -R <number or name>
5173 @itemx --relocated-dump=<number or name>
5174 Displays the contents of the indicated section as a hexadecimal
5175 bytes. A number identifies a particular section by index in the
5176 section table; any other string identifies all sections with that name
5177 in the object file. The contents of the section will be relocated
5178 before they are displayed.
5179
5180 @item -p <number or name>
5181 @itemx --string-dump=<number or name>
5182 Displays the contents of the indicated section as printable strings.
5183 A number identifies a particular section by index in the section table;
5184 any other string identifies all sections with that name in the object file.
5185
5186 @item -z
5187 @itemx --decompress
5188 Requests that the section(s) being dumped by @option{x}, @option{R} or
5189 @option{p} options are decompressed before being displayed. If the
5190 section(s) are not compressed then they are displayed as is.
5191
5192 @item -c
5193 @itemx --archive-index
5194 @cindex Archive file symbol index information
5195 Displays the file symbol index information contained in the header part
5196 of binary archives. Performs the same function as the @option{t}
5197 command to @command{ar}, but without using the BFD library. @xref{ar}.
5198
5199 @item -w[lLiaprmfFsOoRtUuTgAckK]
5200 @itemx --debug-dump[=rawline,=decodedline,=info,=abbrev,=pubnames,=aranges,=macro,=frames,=frames-interp,=str,=str-offsets,=loc,=Ranges,=pubtypes,=trace_info,=trace_abbrev,=trace_aranges,=gdb_index,=addr,=cu_index,=links,=follow-links]
5201 @include debug.options.texi
5202
5203 @item -P
5204 @itemx --process-links
5205 Display the contents of non-debug sections found in separate debuginfo
5206 files that are linked to the main file. This option automatically
5207 implies the @option{-wK} option, and only sections requested by other
5208 command line options will be displayed.
5209
5210 @include ctf.options.texi
5211 @item --ctf-symbols=@var{section}
5212 @item --ctf-strings=@var{section}
5213 Specify the name of another section from which the CTF file can inherit
5214 strings and symbols. By default, the @code{.symtab} and its linked
5215 string table are used.
5216
5217 If either of @option{--ctf-symbols} or @option{--ctf-strings} is specified, the
5218 other must be specified as well.
5219
5220 @item -I
5221 @itemx --histogram
5222 Display a histogram of bucket list lengths when displaying the contents
5223 of the symbol tables.
5224
5225 @item -v
5226 @itemx --version
5227 Display the version number of readelf.
5228
5229 @item -W
5230 @itemx --wide
5231 Don't break output lines to fit into 80 columns. By default
5232 @command{readelf} breaks section header and segment listing lines for
5233 64-bit ELF files, so that they fit into 80 columns. This option causes
5234 @command{readelf} to print each section header resp. each segment one a
5235 single line, which is far more readable on terminals wider than 80 columns.
5236
5237 @item -T
5238 @itemx --silent-truncation
5239 Normally when readelf is displaying a symbol name, and it has to
5240 truncate the name to fit into an 80 column display, it will add a
5241 suffix of @code{[...]} to the name. This command line option
5242 disables this behaviour, allowing 5 more characters of the name to be
5243 displayed and restoring the old behaviour of readelf (prior to release
5244 2.35).
5245
5246 @item -H
5247 @itemx --help
5248 Display the command-line options understood by @command{readelf}.
5249
5250 @end table
5251
5252 @c man end
5253
5254 @ignore
5255 @c man begin SEEALSO readelf
5256 objdump(1), and the Info entries for @file{binutils}.
5257 @c man end
5258 @end ignore
5259
5260 @node elfedit
5261 @chapter elfedit
5262
5263 @cindex Update ELF header
5264 @kindex elfedit
5265
5266 @c man title elfedit update ELF header and program property of ELF files
5267
5268 @smallexample
5269 @c man begin SYNOPSIS elfedit
5270 elfedit [@option{--input-mach=}@var{machine}]
5271 [@option{--input-type=}@var{type}]
5272 [@option{--input-osabi=}@var{osabi}]
5273 [@option{--input-abiversion=}@var{version}]
5274 @option{--output-mach=}@var{machine}
5275 @option{--output-type=}@var{type}
5276 @option{--output-osabi=}@var{osabi}
5277 @option{--output-abiversion=}@var{version}
5278 @option{--enable-x86-feature=}@var{feature}
5279 @option{--disable-x86-feature=}@var{feature}
5280 [@option{-v}|@option{--version}]
5281 [@option{-h}|@option{--help}]
5282 @var{elffile}@dots{}
5283 @c man end
5284 @end smallexample
5285
5286 @c man begin DESCRIPTION elfedit
5287
5288 @command{elfedit} updates the ELF header and program property of ELF
5289 files which have the matching ELF machine and file types. The options
5290 control how and which fields in the ELF header and program property
5291 should be updated.
5292
5293 @var{elffile}@dots{} are the ELF files to be updated. 32-bit and
5294 64-bit ELF files are supported, as are archives containing ELF files.
5295 @c man end
5296
5297 @c man begin OPTIONS elfedit
5298
5299 The long and short forms of options, shown here as alternatives, are
5300 equivalent. At least one of the @option{--output-mach},
5301 @option{--output-type}, @option{--output-osabi},
5302 @option{--output-abiversion},
5303 @option{--enable-x86-feature} and @option{--disable-x86-feature}
5304 options must be given.
5305
5306 @table @env
5307
5308 @item --input-mach=@var{machine}
5309 Set the matching input ELF machine type to @var{machine}. If
5310 @option{--input-mach} isn't specified, it will match any ELF
5311 machine types.
5312
5313 The supported ELF machine types are, @var{i386}, @var{IAMCU}, @var{L1OM},
5314 @var{K1OM} and @var{x86-64}.
5315
5316 @item --output-mach=@var{machine}
5317 Change the ELF machine type in the ELF header to @var{machine}. The
5318 supported ELF machine types are the same as @option{--input-mach}.
5319
5320 @item --input-type=@var{type}
5321 Set the matching input ELF file type to @var{type}. If
5322 @option{--input-type} isn't specified, it will match any ELF file types.
5323
5324 The supported ELF file types are, @var{rel}, @var{exec} and @var{dyn}.
5325
5326 @item --output-type=@var{type}
5327 Change the ELF file type in the ELF header to @var{type}. The
5328 supported ELF types are the same as @option{--input-type}.
5329
5330 @item --input-osabi=@var{osabi}
5331 Set the matching input ELF file OSABI to @var{osabi}. If
5332 @option{--input-osabi} isn't specified, it will match any ELF OSABIs.
5333
5334 The supported ELF OSABIs are, @var{none}, @var{HPUX}, @var{NetBSD},
5335 @var{GNU}, @var{Linux} (alias for @var{GNU}),
5336 @var{Solaris}, @var{AIX}, @var{Irix},
5337 @var{FreeBSD}, @var{TRU64}, @var{Modesto}, @var{OpenBSD}, @var{OpenVMS},
5338 @var{NSK}, @var{AROS} and @var{FenixOS}.
5339
5340 @item --output-osabi=@var{osabi}
5341 Change the ELF OSABI in the ELF header to @var{osabi}. The
5342 supported ELF OSABI are the same as @option{--input-osabi}.
5343
5344 @item --input-abiversion=@var{version}
5345 Set the matching input ELF file ABIVERSION to @var{version}.
5346 @var{version} must be between 0 and 255. If @option{--input-abiversion}
5347 isn't specified, it will match any ELF ABIVERSIONs.
5348
5349 @item --output-abiversion=@var{version}
5350 Change the ELF ABIVERSION in the ELF header to @var{version}.
5351 @var{version} must be between 0 and 255.
5352
5353 @item --enable-x86-feature=@var{feature}
5354 Set the @var{feature} bit in program property in @var{exec} or @var{dyn}
5355 ELF files with machine types of @var{i386} or @var{x86-64}. The
5356 supported features are, @var{ibt}, @var{shstk}, @var{lam_u48} and
5357 @var{lam_u57}.
5358
5359 @item --disable-x86-feature=@var{feature}
5360 Clear the @var{feature} bit in program property in @var{exec} or
5361 @var{dyn} ELF files with machine types of @var{i386} or @var{x86-64}.
5362 The supported features are the same as @option{--enable-x86-feature}.
5363
5364 Note: @option{--enable-x86-feature} and @option{--disable-x86-feature}
5365 are available only on hosts with @samp{mmap} support.
5366
5367 @item -v
5368 @itemx --version
5369 Display the version number of @command{elfedit}.
5370
5371 @item -h
5372 @itemx --help
5373 Display the command-line options understood by @command{elfedit}.
5374
5375 @end table
5376
5377 @c man end
5378
5379 @ignore
5380 @c man begin SEEALSO elfedit
5381 readelf(1), and the Info entries for @file{binutils}.
5382 @c man end
5383 @end ignore
5384
5385 @node Common Options
5386 @chapter Common Options
5387
5388 The following command-line options are supported by all of the
5389 programs described in this manual.
5390
5391 @c man begin OPTIONS
5392 @table @env
5393 @include at-file.texi
5394 @c man end
5395
5396 @item --help
5397 Display the command-line options supported by the program.
5398
5399 @item --version
5400 Display the version number of the program.
5401
5402 @c man begin OPTIONS
5403 @end table
5404 @c man end
5405
5406 @node Selecting the Target System
5407 @chapter Selecting the Target System
5408
5409 You can specify two aspects of the target system to the @sc{gnu}
5410 binary file utilities, each in several ways:
5411
5412 @itemize @bullet
5413 @item
5414 the target
5415
5416 @item
5417 the architecture
5418 @end itemize
5419
5420 In the following summaries, the lists of ways to specify values are in
5421 order of decreasing precedence. The ways listed first override those
5422 listed later.
5423
5424 The commands to list valid values only list the values for which the
5425 programs you are running were configured. If they were configured with
5426 @option{--enable-targets=all}, the commands list most of the available
5427 values, but a few are left out; not all targets can be configured in at
5428 once because some of them can only be configured @dfn{native} (on hosts
5429 with the same type as the target system).
5430
5431 @menu
5432 * Target Selection::
5433 * Architecture Selection::
5434 @end menu
5435
5436 @node Target Selection
5437 @section Target Selection
5438
5439 A @dfn{target} is an object file format. A given target may be
5440 supported for multiple architectures (@pxref{Architecture Selection}).
5441 A target selection may also have variations for different operating
5442 systems or architectures.
5443
5444 The command to list valid target values is @samp{objdump -i}
5445 (the first column of output contains the relevant information).
5446
5447 Some sample values are: @samp{a.out-hp300bsd}, @samp{ecoff-littlemips},
5448 @samp{a.out-sunos-big}.
5449
5450 You can also specify a target using a configuration triplet. This is
5451 the same sort of name that is passed to @file{configure} to specify a
5452 target. When you use a configuration triplet as an argument, it must be
5453 fully canonicalized. You can see the canonical version of a triplet by
5454 running the shell script @file{config.sub} which is included with the
5455 sources.
5456
5457 Some sample configuration triplets are: @samp{m68k-hp-bsd},
5458 @samp{mips-dec-ultrix}, @samp{sparc-sun-sunos}.
5459
5460 @subheading @command{objdump} Target
5461
5462 Ways to specify:
5463
5464 @enumerate
5465 @item
5466 command-line option: @option{-b} or @option{--target}
5467
5468 @item
5469 environment variable @code{GNUTARGET}
5470
5471 @item
5472 deduced from the input file
5473 @end enumerate
5474
5475 @subheading @command{objcopy} and @command{strip} Input Target
5476
5477 Ways to specify:
5478
5479 @enumerate
5480 @item
5481 command-line options: @option{-I} or @option{--input-target}, or @option{-F} or @option{--target}
5482
5483 @item
5484 environment variable @code{GNUTARGET}
5485
5486 @item
5487 deduced from the input file
5488 @end enumerate
5489
5490 @subheading @command{objcopy} and @command{strip} Output Target
5491
5492 Ways to specify:
5493
5494 @enumerate
5495 @item
5496 command-line options: @option{-O} or @option{--output-target}, or @option{-F} or @option{--target}
5497
5498 @item
5499 the input target (see ``@command{objcopy} and @command{strip} Input Target'' above)
5500
5501 @item
5502 environment variable @code{GNUTARGET}
5503
5504 @item
5505 deduced from the input file
5506 @end enumerate
5507
5508 @subheading @command{nm}, @command{size}, and @command{strings} Target
5509
5510 Ways to specify:
5511
5512 @enumerate
5513 @item
5514 command-line option: @option{--target}
5515
5516 @item
5517 environment variable @code{GNUTARGET}
5518
5519 @item
5520 deduced from the input file
5521 @end enumerate
5522
5523 @node Architecture Selection
5524 @section Architecture Selection
5525
5526 An @dfn{architecture} is a type of @sc{cpu} on which an object file is
5527 to run. Its name may contain a colon, separating the name of the
5528 processor family from the name of the particular @sc{cpu}.
5529
5530 The command to list valid architecture values is @samp{objdump -i} (the
5531 second column contains the relevant information).
5532
5533 Sample values: @samp{m68k:68020}, @samp{mips:3000}, @samp{sparc}.
5534
5535 @subheading @command{objdump} Architecture
5536
5537 Ways to specify:
5538
5539 @enumerate
5540 @item
5541 command-line option: @option{-m} or @option{--architecture}
5542
5543 @item
5544 deduced from the input file
5545 @end enumerate
5546
5547 @subheading @command{objcopy}, @command{nm}, @command{size}, @command{strings} Architecture
5548
5549 Ways to specify:
5550
5551 @enumerate
5552 @item
5553 deduced from the input file
5554 @end enumerate
5555
5556 @node debuginfod
5557 @chapter debuginfod
5558 @cindex separate debug files
5559
5560 debuginfod is a web service that indexes ELF/DWARF debugging resources
5561 by build-id and serves them over HTTP. For more information see:
5562 @emph{https://sourceware.org/elfutils/Debuginfod.html}
5563
5564 Binutils can be built with the debuginfod client library
5565 @code{libdebuginfod} using the @option{--with-debuginfod} configure option.
5566 This option is enabled by default if @code{libdebuginfod} is installed
5567 and found at configure time. This allows @command{objdump} and
5568 @command{readelf} to automatically query debuginfod servers for
5569 separate debug files when the files are otherwise not found.
5570
5571 debuginfod is packaged with elfutils, starting with version 0.178.
5572 You can get the latest version from `https://sourceware.org/elfutils/'.
5573
5574 The DWARF info dumping tools (@command{readelf} and @command{objdump})
5575 have options to control when they should access the debuginfod
5576 servers. By default this access is enabled.
5577
5578 @node Reporting Bugs
5579 @chapter Reporting Bugs
5580 @cindex bugs
5581 @cindex reporting bugs
5582
5583 Your bug reports play an essential role in making the binary utilities
5584 reliable.
5585
5586 Reporting a bug may help you by bringing a solution to your problem, or
5587 it may not. But in any case the principal function of a bug report is
5588 to help the entire community by making the next version of the binary
5589 utilities work better. Bug reports are your contribution to their
5590 maintenance.
5591
5592 In order for a bug report to serve its purpose, you must include the
5593 information that enables us to fix the bug.
5594
5595 @menu
5596 * Bug Criteria:: Have you found a bug?
5597 * Bug Reporting:: How to report bugs
5598 @end menu
5599
5600 @node Bug Criteria
5601 @section Have You Found a Bug?
5602 @cindex bug criteria
5603
5604 If you are not sure whether you have found a bug, here are some guidelines:
5605
5606 @itemize @bullet
5607 @cindex fatal signal
5608 @cindex crash
5609 @item
5610 If a binary utility gets a fatal signal, for any input whatever, that is
5611 a bug. Reliable utilities never crash.
5612
5613 @cindex error on valid input
5614 @item
5615 If a binary utility produces an error message for valid input, that is a
5616 bug.
5617
5618 @item
5619 If you are an experienced user of binary utilities, your suggestions for
5620 improvement are welcome in any case.
5621 @end itemize
5622
5623 @node Bug Reporting
5624 @section How to Report Bugs
5625 @cindex bug reports
5626 @cindex bugs, reporting
5627
5628 A number of companies and individuals offer support for @sc{gnu}
5629 products. If you obtained the binary utilities from a support
5630 organization, we recommend you contact that organization first.
5631
5632 You can find contact information for many support companies and
5633 individuals in the file @file{etc/SERVICE} in the @sc{gnu} Emacs
5634 distribution.
5635
5636 @ifset BUGURL
5637 In any event, we also recommend that you send bug reports for the binary
5638 utilities to @value{BUGURL}.
5639 @end ifset
5640
5641 The fundamental principle of reporting bugs usefully is this:
5642 @strong{report all the facts}. If you are not sure whether to state a
5643 fact or leave it out, state it!
5644
5645 Often people omit facts because they think they know what causes the
5646 problem and assume that some details do not matter. Thus, you might
5647 assume that the name of a file you use in an example does not matter.
5648 Well, probably it does not, but one cannot be sure. Perhaps the bug is
5649 a stray memory reference which happens to fetch from the location where
5650 that pathname is stored in memory; perhaps, if the pathname were
5651 different, the contents of that location would fool the utility into
5652 doing the right thing despite the bug. Play it safe and give a
5653 specific, complete example. That is the easiest thing for you to do,
5654 and the most helpful.
5655
5656 Keep in mind that the purpose of a bug report is to enable us to fix the bug if
5657 it is new to us. Therefore, always write your bug reports on the assumption
5658 that the bug has not been reported previously.
5659
5660 Sometimes people give a few sketchy facts and ask, ``Does this ring a
5661 bell?'' This cannot help us fix a bug, so it is basically useless. We
5662 respond by asking for enough details to enable us to investigate.
5663 You might as well expedite matters by sending them to begin with.
5664
5665 To enable us to fix the bug, you should include all these things:
5666
5667 @itemize @bullet
5668 @item
5669 The version of the utility. Each utility announces it if you start it
5670 with the @option{--version} argument.
5671
5672 Without this, we will not know whether there is any point in looking for
5673 the bug in the current version of the binary utilities.
5674
5675 @item
5676 Any patches you may have applied to the source, including any patches
5677 made to the @code{BFD} library.
5678
5679 @item
5680 The type of machine you are using, and the operating system name and
5681 version number.
5682
5683 @item
5684 What compiler (and its version) was used to compile the utilities---e.g.
5685 ``@code{gcc-2.7}''.
5686
5687 @item
5688 The command arguments you gave the utility to observe the bug. To
5689 guarantee you will not omit something important, list them all. A copy
5690 of the Makefile (or the output from make) is sufficient.
5691
5692 If we were to try to guess the arguments, we would probably guess wrong
5693 and then we might not encounter the bug.
5694
5695 @item
5696 A complete input file, or set of input files, that will reproduce the
5697 bug. If the utility is reading an object file or files, then it is
5698 generally most helpful to send the actual object files.
5699
5700 If the source files were produced exclusively using @sc{gnu} programs
5701 (e.g., @command{gcc}, @command{gas}, and/or the @sc{gnu} @command{ld}), then it
5702 may be OK to send the source files rather than the object files. In
5703 this case, be sure to say exactly what version of @command{gcc}, or
5704 whatever, was used to produce the object files. Also say how
5705 @command{gcc}, or whatever, was configured.
5706
5707 @item
5708 A description of what behavior you observe that you believe is
5709 incorrect. For example, ``It gets a fatal signal.''
5710
5711 Of course, if the bug is that the utility gets a fatal signal, then we
5712 will certainly notice it. But if the bug is incorrect output, we might
5713 not notice unless it is glaringly wrong. You might as well not give us
5714 a chance to make a mistake.
5715
5716 Even if the problem you experience is a fatal signal, you should still
5717 say so explicitly. Suppose something strange is going on, such as your
5718 copy of the utility is out of sync, or you have encountered a bug in
5719 the C library on your system. (This has happened!) Your copy might
5720 crash and ours would not. If you told us to expect a crash, then when
5721 ours fails to crash, we would know that the bug was not happening for
5722 us. If you had not told us to expect a crash, then we would not be able
5723 to draw any conclusion from our observations.
5724
5725 @item
5726 If you wish to suggest changes to the source, send us context diffs, as
5727 generated by @command{diff} with the @option{-u}, @option{-c}, or @option{-p}
5728 option. Always send diffs from the old file to the new file. If you
5729 wish to discuss something in the @command{ld} source, refer to it by
5730 context, not by line number.
5731
5732 The line numbers in our development sources will not match those in your
5733 sources. Your line numbers would convey no useful information to us.
5734 @end itemize
5735
5736 Here are some things that are not necessary:
5737
5738 @itemize @bullet
5739 @item
5740 A description of the envelope of the bug.
5741
5742 Often people who encounter a bug spend a lot of time investigating
5743 which changes to the input file will make the bug go away and which
5744 changes will not affect it.
5745
5746 This is often time consuming and not very useful, because the way we
5747 will find the bug is by running a single example under the debugger
5748 with breakpoints, not by pure deduction from a series of examples.
5749 We recommend that you save your time for something else.
5750
5751 Of course, if you can find a simpler example to report @emph{instead}
5752 of the original one, that is a convenience for us. Errors in the
5753 output will be easier to spot, running under the debugger will take
5754 less time, and so on.
5755
5756 However, simplification is not vital; if you do not want to do this,
5757 report the bug anyway and send us the entire test case you used.
5758
5759 @item
5760 A patch for the bug.
5761
5762 A patch for the bug does help us if it is a good one. But do not omit
5763 the necessary information, such as the test case, on the assumption that
5764 a patch is all we need. We might see problems with your patch and decide
5765 to fix the problem another way, or we might not understand it at all.
5766
5767 Sometimes with programs as complicated as the binary utilities it is
5768 very hard to construct an example that will make the program follow a
5769 certain path through the code. If you do not send us the example, we
5770 will not be able to construct one, so we will not be able to verify that
5771 the bug is fixed.
5772
5773 And if we cannot understand what bug you are trying to fix, or why your
5774 patch should be an improvement, we will not install it. A test case will
5775 help us to understand.
5776
5777 @item
5778 A guess about what the bug is or what it depends on.
5779
5780 Such guesses are usually wrong. Even we cannot guess right about such
5781 things without first using the debugger to find the facts.
5782 @end itemize
5783
5784 @node GNU Free Documentation License
5785 @appendix GNU Free Documentation License
5786
5787 @include fdl.texi
5788
5789 @node Binutils Index
5790 @unnumbered Binutils Index
5791
5792 @printindex cp
5793
5794 @bye